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ECLECTIC EDUCATIONAL SERIES 


THE 


ELEMENTS 

OF 

« 

AGRICULTURAL GEOLOGY 


For the Schools of Kansas 


WM. K. KEDZIE, M.S. 


Of the Kansas State Agricultural College 



WILSON, HINKLE & CO. 

137 Walnut Street 28 Bond Street 



CINCINNATI 


NEW YORK 




ECLECTIC EDUCATIONAL SERIES 


Science, History, Languages, etc. 


Norton s Natural Philosophy 
Norton's Elements of Physics 
Schuyler's Principles of Logic 
Hepburn's Manual of English Rhetoric 
Brown's Physiology and Hygiene 
Andrews’s Manual of the Constitution 
Thalheimer s Historical Series 
Venable’s United States History 
Bartholomew's Latin Grammar 
Bartholomew's Latin Gradual 
Bartholomew’s Caesar 
Dujfet’s Erench Method 
Duffet's French Literature, etc. 

Descriptive Circulars and Price-List on application to the Publishers 


Copyright 

1877 

by Wilson, Hinkle & Co. 


Electrotyped at 
Franklin Type Foundry 
Cincinnati 


Eclectic Press 
Wilson, Hinkle & Co. 
Cincinnati 








PREFACE. 


The preparation of this little work, has been under¬ 
taken at the very urgent solicitation of the State Super¬ 
intendent of Public Instruction, and at that of other 
prominent educational workers. Two objects have been 
held in view: 

First: To place in the hands of teachers a book which 
would enable them to meet the requirements for the 
“A” certificate, as given in Article VI, Section 6, of the 
Session-laws of 1876, which requires, among other things, 
that the applicant shall be familiar with “the elements 
of geology, so far as relates to the manner of formation 
of soils and their adaptation to purposes of production.” 

Second: To arrange the work for use in the instruction 
of the more advanced pupils of the common schools. 

To the latter end, it has seemed best to keep the book 
entirely simple and untechnical in its character and lan¬ 
guage. Common names are therefore preferred to tech¬ 
nical terms, and the latter, as a rule, are only used paren¬ 
thetically. The wants of Kansas teachers and students 

have been regarded above all else; and special attention 

(Hi) 



I 


iv PREFACE. 

has been given to the geology, mineral resources, and 
farm soils of this State. 

At the outset of the work, the author was, very natu¬ 
rally, embarrassed by the fact that, although knowing of 
no book having similar objects in view, much of the 
work had already been notably performed, in different 
fields, by Professors J. D. Dana and S. W. Johnson. 
The author, therefore, addressed these gentlemen, stating 
the case, and received from them full permission to make 
such use of their writings as might be found necessary 
to the ends in view. It will only be necessary, then, to 
state explicitly that most of the elementary geology, in 
Part First, is based upon Professor Dana’s “Manual of 
Geology;” and that much of the origin and classification 
of soils, in Part Second, is founded on the chapter on 
soils, in Professor Johnson’s “How Crops Feed.” 

The author desires also to express his obligations to 
Professor B. F. Mudge, Judge F. G. Adams, General 
John Fraser; and, above all, to Professor Orestes St. John, 
for many kind suggestions; also, to Hon. Alfred Gray, 
for use of the geological map of the State. 


TABLE OF CONTENTS 


PART FIRST. 

ELEMENTARY GEOLOGY. 

SECTION I. 

Page 

Formation of the Earth’s Crust.n 

SECTION II. 

I. Mineral Elements of the Rocks.15 

II. Classification of the Rocks.19 

III. Structure of the Rocks . ..22 

SECTION III. 

Geological Ages ......... 27 

I. Age without Life, or Azoic Age.29 

II. Age of Mollusks, or Silurian Age ..... 29 

III. Age of Fishes, or Devonian Age ..... 32 

IV. Age of Coal Plants, or Carboniferous Age . . . 33 

V. Age of Reptiles, or Mesozoic Age .... 36 

VI. Age of Mammals, or Cenozoic Age .... 37 

VII. Age of Man ..39 

SECTION IV. 

I. The Geology of Kansas.43 

II. Mineral Resources of Kansas.48 

(v) 








VI 


TABLE OF CONTENTS . 


PART SECOND. 

ORIGIN AND FORMATION OF SOILS. 

SECTION I. 

Page 

Conversion of Rocks into Soils . . . . . . 55 

I. Changes of Temperature ...... 56 

II. Moving Water.57 

III. Moving Ice .. *59 

IV. Weathering Action of Water and Air .... 63 

V. Action of Plant Life.67 

SECTION II. 

Classification of Soils ....... . 71 

I. By their Formation ....... 71 

II. By their Composition ....... 74 

III. By their Physical Properties ...... 76 

IV. By their Position ........ 78 

SECTION III. 

The Farm Soils of Kansas.79 

SECTION IV. 

Relation of Soils to Crops.83 

SECTION V. 

Exhaustion of Soils ........ 89 

Index ........... 93 















NOTICE TO TEACHERS. 


Wherever possible, teachers should construct a map 
of the school-district or township in which the study is 
being pursued, with a careful designation and description 
of the rock strata. A collection of these rocks, and of 
the soils adjoining them, should be made also, as it will 
frequently prove of much assistance in pointing out the 
relations which exist between soils and the rocks from 
which they have been derived. 

As will be seen, this book has been written on the 
supposition that an abundance of specimens, both of soils 
and of the minerals composing them, will be placed in 
the hands of the pupils studying it. Such specimens are 
very important, both for a perfect understanding of the 
subject, and for the interest which they excite. 

Many specimens of soils, and a small portion of the 
minerals, can be obtained in almost any locality in Kansas. 
It may not always be possible, however, to obtain a satis- 

(vii) 



viii NOTICE TO TEA CNEES. 

factory collection; and, wherever it is desired, the author 
will be glad to lend his assistance, and will furnish a 
complete set of the soils and minerals described in the 
book, charging only for the actual cost of collection. 
Any communications may be sent to his address as given 
below. 

Wm. K. Kedzie, 

State Agricultural College, 

Manhattan , Kansas. 


PART FIRST. 


ELEMENTARY GEOLOGY. 










ELEMENTARY GEOLOGY. 


SECTION I. 

FORMATION OF THE EARTH’S CRUST. 


1. Definition.—Geology is that science which treats of 
the structure of the earth; of its history, of the composition 
of its rocks, and of the causes which have formed them 
and placed them in position. 

2. The Earth.—The earth on which we live is, in 
shape, a globe or sphere, about 25,000 miles in circum¬ 
ference, and slightly flattened at its poles. The average 
diameter of the earth is about 8000 miles; its diameter 
from one pole to another being about 26^ miles less than 
its diameter through the equator. Hence, we know it to 
be slightly flattened. 

3. The Earth once a molten mass.— Geology 
teaches us that countless ages ago the whole earth was a 
mass of melted matter; that from the intense heat which 
then prevailed, all rocks and all solid matter were in a 
liquid condition. The earth must then have reached its 
present state through a process of cooling; a crust of solid 
rock, slowly increasing in thickness, would thus be formed 
over its entire surface. Much of the earth’s interior is 
even now supposed to be in a molten condition, because 
over many portions of the globe large quantities of melted 
rock are frequently thrown out from volcanoes. It is not 

(") 




12 


AGRICULTURAL GEOLOGY. 


generally believed that the whole of the earth’s interior is 
in a liquid state, but that there are large internal seas of 
melted matter, each finding its escape through one or 
more volcanic openings. 

4. Contraction of the Earth’s crust.—As this cool¬ 
ing process continued, the exterior crust of solid rock 
would gradually increase in thickness. But we know that 
nearly all bodies, in the process of cooling from a high 
temperature, shrink or contract powerfully, and tend to 
grow smaller in bulk. Hence, the first rock crust of the 
earth would not long remain smooth and even upon its 
surface, but by the force of contraction would become 
folded, wrinkled, and uneven in appearance. Portions 
would become pressed up into great folds, by which high 
hills and mountain ranges would be formed; other por¬ 
tions would be depressed by the same force much below 
their first level, and would thus produce valleys and ocean 
beds. Between these two extremes we would find every 
variety of low-lands and high table-lands. 

5. Changes slight compared with the Earth’s 
mass.— While these elevations and depressions of the 
earth’s crust appear very great to our eyes, they are really 
very insignificant when compared with the entire mass of 
the earth itself. It is about 4000 miles from the circum¬ 
ference to the center of the earth; but the deepest ocean 
sounding is only about 50,000 feet below water level, and 
the highest mountain peak (Everest) but 30,000 feet above 
it. The mass of mountain ranges is also comparatively 
small; the entire range of the Pyrenees, spread over Eu¬ 
rope, would raise the surface but six feet. Thus we see 
that the mountain ranges and ocean beds upon the earth’s 
surface are really much less in proportion than the folds 
and wrinkles upon the surface of an orange. 


FORMA TION OF ROCK LA YERS. 


T 3 


6 . Formation of Rock Layers.—These changes of 
level which are here described must have taken place very 
gradually, extending many thousands of years through the 
earth’s geological history. As soon as the surface crust be¬ 
came sufficiently cooled, the dense clouds of vapor of water, 
which had surrounded the earth like a mantle, would be 
deposited upon its surface. Hence, we suppose that nearly, 
if not the whole surface of the earth was at one time 
covered by a shallow ocean. By the constant wearing 
action of the waves of this great ocean, the underlying 
rock crust would be worn away, deposits of fine mate¬ 
rial—small pebbles, sand, clay, etc.—would be formed, 
and thus would begin the 'formation of the first or lowest 
rock layer or bed. Upon this first “stratum,” followed 
the formation of the later rock layers in succession through 
each period of the earth’s history, and thus has been 
made the “basement of rock bed§,” which every-where 
underlies the soil and waters of the earth’s surface. Other 
beds appear to have been formed by the waters of riv¬ 
ers and lakes. Many show the marks of ripples and 
waves made while the rock material was still in the state 
of a fine powder. Some, after having become solidified, 
were cracked by strong upheavals, and the openings 
were filled with melted rock forced up from below. The 
rock layers of the same period differ upon different por¬ 
tions of the earth’s surface, and are not all found at 
any one place. Every indication shows that they must 
have been formed with extreme slowness, accompanied and 
followed by many upheavals and depressions of the earth’s 
crust, and frequently much altered by the action of heat. 
“ These different beds vary from a few feet to hundreds 
of yards in thickness. The different kinds are spread out 
over one another in many alterations. Sometimes they are 


14 , 


AGRICULTURAL GEOLOGY. 


in horizontal layers; but very often they are inclined as 
if they had been pushed or thrown out of their original 
position; and in some regions they are crystallized. By 
careful study of the rocks of different countries, it has 
been found that the series of beds, if all were in one 
pile, would have a thickness of 15 or 18 miles. The 
actual thickness in most countries is far less than this.”— 
Dana. 

7. Interior Rock Crust.— While these rock layers 
have been forming above, the original crust of the earth 
itself must have been steadily cooling and increasing from 
within. But we know almost nothing of this interior rock, 
as it is beyond our reach and observation. 

By careful examination of the rock layers within our 
reach, we are able to describe accurately the changes 
through which the earth has passed from the earliest period 
to the present time. 



SECTION II. 


I. MINERAL ELEMENTS OF THE ROCKS. 

8 . Rocks.—“By the word Rock in Geology is meant 
any formation of rock material, whether solid or other¬ 
wise.”— Dana. Exa?nple. Sandstone is a rock; clay slate is 
a rock. But as all sandstones were first composed of loose 
grains of simple sand, and all slates, of more or less pure 
clay — and these are found in all grades of solidity and 
hardness,—we can not draw an absolute line, but apply 
the word rock to any naturally formed bed, whether of 
solid or of loose earthy material. All rocks are composed 
of one or more minerals. 

g. A Mineral is a natural substance, generally com¬ 
posed of two or more elements, which has a uniform 
structure, and which has not been organized by life.— 
Ex. Quartz and marble are both minerals. There are 
now known about 600 species of minerals. 

10. An Element is any simple substance.— Ex. Iron, 
charcoal, and sulphur are elements. 

11. A Crystal is the natural form of a mineral. A 
rock is said to have a crystalline or crystallized structure 
when the minerals composing it are found in the form of 
crystals. Each mineral has its own peculiar crystalline 
forms which it always assumes. 


(i 5 ) 


16 


AGRICULTURAL GEOLOGY. 


We shall now consider some of the most important min¬ 
erals which go to make up the mass of rocks. 

12. Quartz.— Quartz, also sometimes called Silica , is 
the most abundant mineral known, probably constituting, 
with its compounds, nearly one-half the earth’s crust. 
When pure, it appears like glass, and is found in crystal 
prisms, which have six sides and end in six-sided pyra¬ 
mids. It is very hard, scratching glass easily, and can 
not be melted. Its more impure forms are frequently 
yellow, brown, or black in color. Flint, jasper, and agate 
are varieties of quartz. Sand is also nearly pure quartz, 
as is much of the gravel and pebbles which are washed 
out by streams. 

13. Silica with other Minerals.— A very large and 
important class of minerals consists of compounds of silica 
with other mineral substances. These compounds are 
called Silicates. The following are the most important 
substances which form these compounds: 

14. Aluminum.—This is a beautiful bluish white metal; 
very light, being about as heavy as glass. It is as strong 
as iron, and is remarkably sonorous—that is, when struck 
it rings like a bell. It is only used for jewelry and fine 
instruments, and is very interesting, because, when united 
with the oxygen of the air, it forms: 

15. Alumina;—a white, hard, infusible substance, which 
is the basis of all clays and clay rocks. Emery powder is 
a good example of nearly pure alumina. 

16. Magnesia.—This is most familiar to us in the form 
of calcined magnesia. It is white, infusible, and insoluble. 

17. Lime.—This we all know as ordinary quick-lime. 

18. Potash and Soda. 1 —These are the common alka¬ 
lies. 

19. Oxide of Iron.—This is most familiar to us in its 


TALC OR SOAPSTONE. 


17 


common form of iron rust. It forms part of many min¬ 
erals, and causes the yellow and red color of many soils. 
Sometimes all of these substances, and sometimes only two 
or three of them, are combined together to make the min¬ 
erals called Silicates. We shall consider some of the most 
important. 

20. Feldspar. — This mineral is composed of silica, 
alumina, and potash. A variety called Albite contains 
soda instead of potash. It is a white mineral, sometimes 
having a tinge of red, and splits easily and smoothly in two 
directions. When converted into powder by the action of 
the weather, it forms the principal bulk of all clays. 

21. Kaolinite.—This is pure clay, and is produced from 
feldspar by the wearing action of water, frost, etc. It is 
generally found in the form of a fine, soft, yellowish white 
powder. The various kinds of clay — such as pipe clay, 
brick clay, blue clay, etc.—consist of kaolinite mixed with 
more or less other impurities. 

22. Mica.—This is the mineral commonly, but wrongly, 
called Isinglass. It is a compound of silica, alumina, pot¬ 
ash, lime, magnesia, and oxide of iron. It splits very 
easily into thin, tough leaves, as transparent as glass, which 
are often used in stove doors. 

23. Pyroxene and Hornblende.—Both these minerals 
are compounds principally of silica, magnesia, lime, and 
oxide of iron. They are generally black or greenish black 
in color, although some fine varieties are white. The 
beautiful fibrous mineral called Asbestos is a variety of 
hornblende. 

24. Talc or Soapstone.—This is a compound of silica, 
magnesia, and water. The finer varieties, found in thin 
scales or plates, are called Talc; the coarser varieties, Soap¬ 
stone. The mineral is of a gray or greenish gray color, 

A. G.—2 


13 A CRICUL TURAL GEO LOG Y 

and remarkable for its greasy or soapy feeling,— whence 
its name. 

25. Serpentine is a mineral having the same compo¬ 
sition as talc, but harder, finer grained, and of a rich 
dark green color. 

26. Carbon.— Carbon is an element which is familiar 
to us in three forms: First,—the diamond, the hardest 
substance known; second,— plumbago, commonly called 
black lead; third,—charcoal. All varieties of mineral coal 
consist of nearly pure carbon. 

27. Carbonic Acid.—When carbon in any form is 
burned, it unites with the oxygen of the air and becomes 
a gas called Cai'bonic Acid (properly carbonic anhydride). 
This gas exists in small quantities in the atmosphere— 
about 4 to 6 parts in 1 0,000. It is produced not only in 
the burning of wood and coal, but is thrown out of the 
lungs of animals in the process of breathing. 

28. Carbonates.—Carbonic acid gas, in the presence 
of water, unites with a large number of other mineral 
substances, and produces a very important class of minerals 
called Carbonates. The following are the more common: 

29. Calcite.— The simplest form of this mineral in 
Kansas is seen in ordinary limestone. Marble is the same 
mineral in its crystalline form. Chalk is still another va¬ 
riety. In all of its forms, this mineral is a compound of 
carbonic acid and lime. When crystallized it splits easily 
in three directions. When any acid (such as. vinegar) is 
poured upon it, it dissolves rapidly with violent bubbling 
from the escape of the carbonic acid gas, which passes off 
again into the air. This mineral forms a very large and 
important part of the rock layers of the earth. 

30. Dolomite is a compound of carbonic acid, lime, 
and magnesia. When found in massive beds, it forms 


ME TAMORPHIC R O CKS. 


J 9 


magnesian limestone , which may be distinguished from com¬ 
mon limestone by its dissolving much more slowly in 
acids. It is a common and important mineral. 

31. Gypsum.—This mineral is a compound of sulphu¬ 
ric acid, lime, and water. It is found in large beds in 
Kansas. When pure it is called Selenite , and is colorless 
and transparent. It is frequently found in compound crys¬ 
tals shaped like arrow-heads. The less pure varieties are 
of a gray or flesh-red color. It is from this mineral that 
plaster of Paris is made. 


II. CLASSIFICATION OF THE ROCKS. 

32. For convenience in the study of the rocks, we can 

easily divide them into classes. We may do this by two 
methods: 1st. By their origin; 2d. By their structure. 

By their origin , we should form three classes of rocks: 
(1) Igneous Rocks; (2) Sedimentary Rocks; (3) Metamor- 
phic Rocks. 

33. Igneous Rocks are those which have been thrown 
out in a melted state, from which they have cooled to their 
present condition. Ex .—Lava from volcanoes. 

34. Sedimentary Rocks, as the name signifies, are 
those which have been formed by the deposit of loose 
fragments, or sediment, such as mud, sand, gravel, etc., 
which have afterward become cemented together into solid 
rock. Ex .—Our common limestones are sedimentary rocks. 
Rocks of this class have generally been deposited under 
water. 

35. Metamorphic Rocks are those which have been 
formed by the deposit of fine particles, or sediment, and 
afterward much altered (metamorphosed) by the action of 


20 


AGRICULRURAL GEOLOGY. 


heat. Where there was only a moderate degree of heat, 
the rock was simply baked into a solid mass; but where 
the heat was very intense, it became crystallized. Ex .— 
White marble is a metamorphic rock, produced by the 
action of heat on Ordinary limestone. From their struct¬ 
ure, we may divide rocks into two classes: ist. Crystalline 
Rocks; 2d. Fragmental Rocks. 

36. Crystalline Rocks are those in which the mate¬ 
rial of which the rock consists has a crystalline structure. 
In the coarse-grained rocks of this class, the crystals are 
easily seen with the naked eye; but in the finer grained 
varieties they are invisible. Crystalline rocks, again, may 
be divided into two classes: ist. Siliceous, or Quartz, 
Rocks; 2d. Calcareous, or Lime, Rocks. Among the 
more common varieties of the first class are: 

37. Granite.—This is a compound rock consisting of 
quartz, feldspar, and mica. It is either light or dark gray, 
or flesh red, according to which of the three ingredients 
is present in greatest quantity. It is found in all grades, 
fine and coarse grained. 

38. Mica Slate differs from granite in containing a 
much larger quantity of mica. This rock is arranged in 
parallel layers, and splits easily into thin slabs of a glisten¬ 
ing gray color. It is frequently used for whetstones. 

39. Clay Slate.—This is a very fine-grained rock, and 
but slightly crystalline in structure. It is found in many 
colors—black, green, red, and gray. It splits very easily 
into smooth, hard sheets, which are used for roofing ma¬ 
terial and for writing-slates. 

40. Talcose Granite differs from ordinary granite in 
containing talc instead of mica. It is grayish or greenish 
in color, and has a greasy feeling. 

41. Talcose Slate contains still more talc, and hence 


SHALES. 


21 


is more smooth and greasy in its feeling. It readily splits 
into grayish-green plates. 

Of the igneous rocks, there are two of special interest: 

42. Trap;—a fine-grained; dark brown or black rock, 
of ancient igneous origin. The Palisades of the Hudson 
River are good examples of trap rock. 

43. Lava.—The word lava is applied to any rock which 
has been thrown in a melted state from a volcano. Modern 
lavas are generally very light and porous in structure. 

The two most important calcareous or lime rocks of the 
crystalline class have already been mentioned, viz:— 

44. Granular Marble;—a crystalline limestone, gen¬ 
erally pure white in color, and composed of glistening 
grains like loaf sugar. 

45. Dolomite ;—which has almost the same appearance 
as granular limestone, but which also contains carbonate of 
of magnesia. 

46. Fragmental Rocks.—These are much the same 
as sedimentary rocks; that is, they have been formed by 
cementing together small particles or fragments of other 
rocks. The more common are: 

47. Conglomerates or Pudding-stones;—which 
have been formed by cementing together very coarse 
fragments or pebbles of many other rocks. The name 
of the conglomerate depends upon the kind of the peb¬ 
bles which principally compose it. 

48. Sandstones;—generally consisting of fine grains 
of quartz sand cemented together into compact rock. 
They sometimes contain other minerals. 

49. Shales ;—rocks composed of compact clay. They 
have the same variety of colors as the slates. The latter 
are shales which have been much altered by heat. All 
shales split easily into thin fragile plates. 


22 


AGRICULTURAL GEOLOGY. 


50. Limestones ; — compact sedimentary rocks, con¬ 
sisting principally of carbonate of lime, but frequently con¬ 
taining small quantities of other minerals. They are gen¬ 
erally of a grayish white color, but are sometimes found 
of a great variety of other colors. The so-called yellow, 
red, and black marbles are simply these colored limestones 
polished. When pure limestone is heated or burned, quick¬ 
lime is obtained. If magnesian or impure limestones are 
burned, they sometimes furnish a hydraulic cement, which 
will harden under water. 


III. STRUCTURE OF THE ROCKS. 

If we examine the immense rock masses of which the 
earth’s crust consists, we shall find them of two kinds,— 
stratified and - unstratified. 

51. Stratified Rocks.—This name is given to those 
rocks which lie in beds or layers; hence their name — 
from the Latin word stratum, (plural, strata ), which means 
spread out. The earth’s rocky strata are spread out in 
beds of vast extent, many of them covering thousands of 
square miles. They are the rocks of nearly the whole 
of the United States and of nearly all North America. 

( Dana.) 

52. Strata.—A stratum, then, would be defined as a 
bed of any one kind of rock. A stratum may be made 
up of still smaller rock beds or plates, which are called 
layers. A number of strata lying one above the other, 
which were formed in a particular geological age, is called 
a formation. 

Stratified rocks show many interesting varieties of struct¬ 
ure. They are said to be: 


UNSTRATIFIED ROCKS. 


23 


(1) Massive , when it is not possible to split them into 
thin slabs. Ex. —Some varieties of granite. 

(2) Schistose , when they break easily into slabs because 
of their crystalline structure. Ex. —Mica slate. 

(3) Laminated , when they may be broken into slabs, but 
not because of their crystalline structure. Ex. — Some 
kinds of limestone are laminated. 

(4) Slaty, when they split easily into thin plates. Ex .— 
Roofing slate. 

(5) Shaly, when they also split readily into thin plates, 
which are irregular and fragile, inclining to break easily. 
Ex. —Clay shale. 

The strata of rocks frequently show peculiar markings, 
which were produced while they were forming. Ripple 
marks are common, and were produced by the gentle flow 
of water over the rock bed while it was still soft and un¬ 
hardened. The prints of rain drops are sometimes found, 
produced while the rock was in the same condition. Mud 
cracks are found in clay rocks, which, in the process of 
drying, frequently crack and split, the cracks afterwards 
becoming filled with some other rock material. 

53. Unstratified Rocks.—Rocks are called unstrati¬ 
fied, which do not give any evidence of having been formed 
in beds or strata. Such are the high trap rocks of Lake 
Superior and.of the Hudson River, and many hills and 
mountains of granite. Perfectly unstratified rocks are found 
in but very few places upon the earth’s surface. We should 
expect this, from our knowledge of the manner in which 
the rocks of the globe were formed. As we have already 
seen in paragraph 6, after the earth had cooled, and a thick 
rock crust had been formed, it became nearly covered by 
the waters of a great ocean, whose waves began to wear 
away and work over the unstratified rock below. The fine 


24 


AGRICULTURAL GEOLOGY. 


material, thus produced, would be afterwards distributed by 
the waters into beds or strata, which would in time, by 
heat and pressure, be hardened into stratified rock. 

Thus, 7 iearly all the unstratified rocks of the globe have 
been covered by those which are stratified. Even granite 
is supposed to have been at first a stratified rock, which 
has lost its structure by the action of intense heat. While 
these stratified rocks are very widely distributed over the 
earth, they are not all found at any one place, nor are 
they the same in all regions. Some strata found in one 
State are unknown in others; and strata formed at the 
same time may in one State be limestones and in another 
sandstones. 

54. Vein Structure. — This is a somewhat uncommon 
formation, which has been made by the rocks becoming 
cracked or fractured, and the openings, thus formed, after¬ 
wards filled up with other rock material. These veins may 
vary in thickness from that of a sheet of tissue paper to 
a width of many yards, and they often contain metals 
and ores. When these breaks have been filled with melted 
rock, forced up from below, they are called dikes. 

55. Positions of the Rock Layers.— Nearly all 
stratified rocks were first deposited in horizontal beds or 
layers. We know this must have been the case because, 
as we have already learned, these rocks were formed by 
the accumulation of fine particles of loose earth, sand, 
mud, etc., distributed by the action of water, either of 
the ocean or of lakes or rivers; very much as the de¬ 
posits we call deltas are now formed at the mouths of 
large rivers. 

In many coal beds, which we know to have once been 
great marshes, trunks of trees have been found standing 
erect and always perpendicular to the general strata. There 


ROCK LAYERS. 


2 5 


is one exception to the formation of horizontal strata, 
which might possibly take place in the case of rivers fall¬ 
ing with a sudden pitch into the ocean, when the deposit 
would of course follow the curve of the river bed. 

56. Upheavals of the Rock Layers. — Though 
these rock beds were horizontal when first formed, very 
few of them are now found in that position. Many of 
them are sharply inclined, and some even stand upon end. 
This arises from the fact, that since the formation of these 
strata they have been tilted up and thrown out of position by 
great upheavals of the earth’s crust. Sometimes these strata 
are bent upon themselves in immense folds, miles in extent, 
and frequently they have been broken squarely in two. 

When strata lie one above the other in parallel layers, 
they are said to be conformable. But when one set of 
strata lies horizontally over another set which has been bent 
or tipped up, the two are unconformable. 

When the edges of a number of strata are thrust out 
of the ground, it is called an outcrop. The angle which 
the outcrop makes with the horizon is called the dip. 
The horizontal direction at right angles with the dip is 
called the strike of the strata. ( Dana .) 

A fault is where strata have been thrown up, broken in 
two, and a part displaced either upward or downward. 
Sometimes where strata have been thrown up in sharply 
curved folds, the upper portion of the fold becomes worn 
away, so that there appear to be the edges of two beds 
in sight, while they are really parts of one formation. In 
consequence of these great upheavals, we may become 
very familiar with the entire strata of the earth, and meas¬ 
ure accurately both their extent and thickness. If they 
had all remained in their first positions, this would be 
impossible; as in that case they would lie far down, 
a. G.—3 


26 


AGRICULTURAL GEOLOG V 


beyond our reach. But no matter how deeply they may 
have once lain, at some point upon the earth’s surface each 
has been upturned by some great disturbance, and placed 
within the easy reach of our observation and study. 

57. Rocks, the Result of Life. — Many of the 
important rock formations of the earth’s crust are plainly 
the result of material furnished by plant and animal life. 
As we shall see hereafter, the immense beds of mineral 
coal are merely the remains of plants. Many limestone 
rocks of the globe are on the other hand plainly of ani¬ 
mal origin, having been directly furnished through their 
remains in the form of shells or stony skeletons. This is 
finely seen in the immense coral reefs of the ocean, some 
of which are even now being built by the remains of 
minute coral animals. Numbers of this class of rocks, 
when examined with a .microscope, will show many frag¬ 
ments of little shells. In others, the shells may have been 
destroyed by the action of heat, or they may have been 
ground to a fine powder by the wearing effects of water, 
and have become solid rock. Some other minute animals, 
and even some plants, have a covering of silica, which, 
gathering from their remains, forms vast siliceous deposits. 


SECTION III. 


GEOLOGICAL AGES. 

58 .—The extensive layers or strata, of which the rock 
formations of the earth consist, may be regarded as so 
many pages which make up a history of the changes 
through which the earth has passed since its creation. 
The strata, which were formed in any one particular 
period of time, are grouped together into what is called 
an Age. We may regard these ages, then, as chapters of 
the earth’s geological history. By careful and minute exam¬ 
ination of the rock formations over many portions of the 
earth, geologists have succeeded in making this history 
very complete and perfect. But it must not be supposed 
that this could be done by the study of the rocks of any 
one country, or even of any one continent. We must 
examine all the rock formations of the earth, as far as 
they can possibly be reached, before we can arrive at any 
reliable conclusions. 

This is necessary for many reasons. We have already 
seen that the rock strata of the same period may differ 
greatly in different countries, or even in different parts of 
the same country, so that without careful study we should 
be misled by this variation. Then, too, by the gigantic 
disturbances and upheavals, of which we learned in the 

(27) 


28 


AGRICULTURAL GEOLOGY. 


last section, these strata have been so thrown out of place 
that we can not often trace them regularly for more than 
a short distance. In many places the strata have been 
almost entirely washed and worn away; and nearly every¬ 
where they are covered with the earth and soil, only crop¬ 
ping out here and there. All these conditions make the 
examination of the strata very difficult, and render it neces¬ 
sary to study them over a great extent of surface. 

59. Fossils.—The most perfect method of determining 
the place or age of any rock layer is by the study of the 
stony remains of the animals and plants which it fre¬ 
quently contains, and which lived and died while the layer 
was being formed. These plant and animal remains are 
called fossils , a word which means that which is dug 
out of the earth. These fossils have been so carefully 
collected and studied that by their aid we are able to tell 
much about the condition of the earth, and of the plants 
and animals which lived upon it during each age or period. 

60. —The geological ages through which the earth has 
passed have been arranged by Professor Dana as follows: 

1 st. Age without Life (Azoic). 

2d. Age of Mollusks (Silurian ). 

3d. Age of Fishes (Devonian). 

4th. Age of Coal Plants (Carbotiiferous). 

5th. Age of Reptiles (Mesozoic). 

6th. Age of Mammals (Cenozoic). 

7 th. Age of Man. 

61. Subdivisions. — In the study of the strata of 
these great ages, we find that there are very sudden 
changes from one stratum to another, which were accom¬ 
panied by almost entire destruction of some kinds of life, 
and by the introduction of others. Hence, we can divide 
some of these ages into smaller portions of time called 


SILURIAN AGE. 


29 


periods , and these again into, still smaller divisions called 
epochs. We shall now briefly examine the geological ages 
of the earth’s history in their order. 


I. AGE WITHOUT LIFE, OR AZOIC AGE. 

62.—As its name signifies, this was the age without 
life; or, if any existed, it must have been of very simple 
kinds, the remains of which have not been preserved in 
the rocks. The Azoic rocks are the oldest of the earth’s 
crust, and they surround the entire globe. They are, 
however, found in few localities, because they have since 
been covered by the various later formations. The great 
Azoic area upon this continent is a vast V-shaped tract, 
extending from a point north of Lake Superior in two 
great arms north-east and north-west. With the exception 
of this great area, and a few small spots or islands, the 
entire continent was covered by the waters of a great and 
apparently lifeless ocean. The rocks of this age are almost 
wholly crystalline in nature—granite, mica slate, quartz 
rocks, and granular limestone. Many large deposits of 
iron ore were made in this age; such are the great beds 
of the Lake Superior region, of Iron Mountain, and of 
Pilot Knob in Missouri. 


II. AGE OF MOLLUSKS, OR SILURIAN AGE. 

63.—The formations of this age were named from the 
Silures, an ancient tribe in Wales. The age is divided 
into two portions, the Lower and Upper Silurian, each of 
which is separated again into periods. 


30 


A GRICUL TURA L GEOLOGY. 


64. Life of the Silurian Age.— The life which first 
appeared upon the earth during this age must, of course, 
have been of the simplest and lowest kinds, and belonged 
wholly to the ocean. The greater part of this continent 
was under the shallow waters of a wide ocean, and there 
were no land plants or animals. The plants of the age 
were all sea-weeds. The animals varied slightly during the 
different periods, but were all sea animals. They consisted 
of radiates, such as corals, star-fishes, etc.; mollusks , soft, 
pulpy animals, usually with a shelly covering, such as our 
river muscles, snails, etc., some of them of immense size, 
having shells ten to fifteen feet long; articulates , or jointed 
animals, the most remarkable of which were the trilobites, 
some of them twenty inches in Jength; and peculiar, 
lobster-like crustaceans , growing from six to eight feet long. 
Sponges were also abundant, and trails of worms are found 
upon the rocks of this age. 

65. Rocks of the Silurian Age. — ( a ) Lower Silu¬ 
rian. — It is probable that, excepting the azoic areas of 
ancient land, the Lower Silurian strata cover nearly the 
whole of this continent, although they are often hidden 
by other formations. Over the interior of the continent, 
the rocks were sandstones below, and magnesian lime¬ 
stones above; while over the eastern portion, the formation 
was principally slate. The sandstones contain ripple marks, 
and the slates, mud cracks, showing that much of the 
continent lay at the bottom of a shallow sea, either as a 
sandy bed or beach, or as a mud flat or bottom. The 
second period of the Lower Silurian was one of the lime¬ 
stone periods of the continent. During the first portion 
of this period, limestones were forming not only over the 
eastern portion, but over the whole of the interior conti¬ 
nental region. Some of these limestones were afterward 


SILURIAN AGE. 


much altered and crystallized by heat, and now con¬ 
stitute the marble quarries of Vermont and Massachu¬ 
setts. During the third period, the region of limestone 
making decreased in size, and over the eastern part of 
the continent, as well as the northern portions of the inte¬ 
rior, the formation of shales and shaly sandstones began; 
while, in other parts, shales and shaly limestones were 
formed. 

While through all these periods gentle and gradual 
changes of level were going on in the earth’s crust, more 
important upheavals took place about this time. Near 
Lake Superior, about the close of the first period, the 
rocks became widely fractured, and large quantities of 
melted rock were forced up, forming the immense trap- 
dikes which are seen there to-day. The Green Mountains, 
the first of the Appalachian Range, now appeared above 
the level of the ocean as dry land. 

(b) Upper Silurian .—There was a great variety in the 
rocks of the first period of the Upper Silurian. They 
were: ist. A conglomerate rock, extending from Central 
New York south to the Appalachian Range. 2d. A soft 
sandstone, extending in the same manner, but still further 
westward, across Michigan. 3d. A hard sandstone, extend¬ 
ing further west still. 4th. A deposit consisting of lime¬ 
stone, over the interior of the continent; shale below and 
limestone above, at Niagara; and shales and limestone 
over the Appalachian region. The rocks of the second 
period of the Upper Silurian are loose sandstones and 
shales, reddish in color, occurring over New York and a 
little to the westward. It is from this formation that 
the rich salt brines of New York are obtained. The rocks 
of the third period of the Upper Silurian are impure 
limestones, confined to New York and the Appalachian 


3 2 


AGRICULTURAL GEOLOGY. 


region. At the close of the Silurian age, half of New 
York and most of Canada and Wisconsin had become dry 
land. Michigan was still under water. 


III. AGE OF FISHES, OR DEVONIAN AGE. 

66 . — The formations of this age were named after the 
principal rocks in Devonshire, Great Britain. The age is 
remarkable for the first appearance upon the globe of land 
plants, of insects, and of fishes. The latter were the first 
vertebrate animals, or those having a backbone. 

67. Life of the Devonian Age.—The most remark¬ 
able plants of this age were enormous ferns, lycopodiums 
(ground pines'), tree rushes growing over twenty feet 
high, and trees closely resembling our modern pines. The 
animals of the age included many forms similar to those 
of the preceding ages; but the age was especially interest¬ 
ing for its immense coral formations, the greatest in the 
earth’s history. Here also are found the first insects. 
The fishes, which here first appear, belonged to the two 
classes: — the selacians or sharks, and the ganoids or 
sturgeons, gar-pikes, etc. Some of the last class were of 
great size, and their appearance at this early time is of 
great interest, inasmuch as they present many peculiarities 
of structure, which seemed to foreshadow the varied forms 
of vertebrate life that were to appear in the geological 
ages to come. 

68. Rocks of the Devonian Age.—The rocks of 
this age may be included in the formations of five periods: 

1st. A sandstone (the Oriskany), stretching from the 
Appalachian region northward into New York and west¬ 
ward to the Mississippi, where it is represented by a 
limestone deposit. 


CARBONIFEROUS AGE. 


33 


2d. A formation consisting of a layer of grit rock 
below, and an upper layer of coral-formed limestone, 
extending from New York westward beyond the Missis¬ 
sippi (Corniferous.) 

3d. A formation of sandstone and shale, and layers of 
limestone; also extending from New York westward, 
where it exists mainly as limestone. (Hamilton.) 

4th. Principally consisting of sandstone, over Southern 
New York. (Chemung.) 

5th. Comprising the sandstones and shales of Pennsyl¬ 
vania. (Catskill.) 

IV. AGE OF COAL PLANTS, OR CARBONIFEROUS AGE. 

69. —This age is named from the great coal beds which 
it contains. The rock strata of the age show that, in its first 
portion, the continents were almost wholly covered by seas. 
That, in the next period, there was an elevation of a part 
of the land above the sea level, forming immense stretches 
of marshy country, which were covered with a luxuriant 
growth of vegetation, where the coal beds were formed; 
but that, even at this period, there were alternate elevations 
above water level, and depressions below it, as shown by 
the coal being in seams, alternating with other marine 
rock strata. Finally, in the closing period, the oceans 
again covered much of the land, though not to so great 
an extent as in the preceding ages. 

70. Life of the Carboniferous Age.— The great 
marshy districts and floating islands of the Carboniferous 
age were covered with a wonderfully dense growth of 
vegetation, mostly of flowerless plants; tree ferns, growing 
to the height of twenty feet, lycopodiums, and tree rushes. 
Among flowering plants, there were trees related to our 



34 


A GRICUL TURAL GEOLOG \ r . 


pines; and great trees, called Sigillarids ,- growing to a 
height of sixty feet. Remains of fruits and nuts have 
also been found. Among the animals also, of this age, 
there appeared to be much progress. Besides insects, there 
existed centipedes and scorpions; and among vertebrates, 
in addition to the usual variety of fishes, there were found, 
for the first time, reptiles, as shown by their remains and 
foot-prints found in the rocks. 

71. Rocks of the Carboniferous Age.—The rock 
strata of this age are divided into three periods: 

(a) Lower Carboniferous. —Over the interior of the con¬ 
tinent, the rocks of this period were mostly limestones, 
while, upon the eastern border, they were sandstones and 
marls, with some limestones. 

if) Upper Carbonife 7 'ous Period. — The formations of this 
periQd were sandstones, shales, conglomerates, and lime¬ 
stones. Between these strata occur the seams of coal in 
occasional beds; but the entire coal seams, taken together, 
are not one-fiftieth of the thickness of the formation. 

(e) The Last or Permian Period. — These rocks are mainly 
sandstones and impure limestones, with some gypsum. 
They cover many portions of the interior, especially in 
Kansas, and occasionally contain thin seams of coal. 

72. Coal Formations.— As already stated, the indi¬ 
cations are plain that this age was one of numerous 
changes of level; that all regions, over which the forma¬ 
tion of coal was going on, were at long intervals of time 
depressed below the sea level, so that coal forming was 
for the time checked, and layers of marine rock were 
deposited ; that when the land was again elevated to the 
condition of a marsh, the thick growth of vegetation and 
the making of coal began again, and thus there were 
formed alternate coal beds and marine rock layers. The 



COAL FORMATIONS. 


35 


extent of the coal deposits over the earth show that the 
climate of the age was wonderfully adapted to plant growth; 
the atmosphere was warm and uniform, and laden with 
moisture. Coal beds were formed by the accumulation of 
vegetable matter, which was afterwards partly decomposed 
under great pressure. 

Over these great coal marshes were constantly gathering 
fallen leaves, dead parts of plants, etc., after long ages, 
making deposits of great thickness. By the pressure of 
the mass above, the layers below, while slowly decom¬ 
posing, were forced into a more compact state. Finally, 
when the entire region became lowered, the ocean over¬ 
flowed it, and thick beds of marine rock were for ages 
formed above it. The immense pressure and smothered 
decay forced out the light gases of the vegetable matter, 
and left behind a bed of nearly pure carbon or coal. A 
depth of from eight to twelve feet of vegetable matter 
would be needed to make one foot of coal. Coal beds 
vary in thickness from a fraction of an inch to over forty 
feet. These beds sometimes contain large erect trunks of 
trees changed to coal. The kind of coal depends some¬ 
what upon the extent to which the pressure has been car¬ 
ried, and upon the heat to which the bed may have been 
exposed. Bituminous coal is that containing much bitumen, 
or pitchy substances; it burns with a bright flame. Anthra¬ 
cite coal is a hard, compact variety, with little or no bitu¬ 
men ; it produces great heat, but very little flame. Cannel 
coal is a compact, bituminous variety. The rock layers 
just above and below coal beds are frequently soft shales— 
those above often being full of impressions of leaves and 
twigs. 


36 


A GRICUL TURAL GEO LOG V 


V. AGE OF REPTILES, OR MESOZOIC AGE. 

73. — This age is named from the immense number and 
great size of the reptiles which then existed. It is divided 
into three periods, Triassic, Jurassic, and Cretaceous. 

74. Life of the Reptilian Age. — Among plants, 
there were found in the first two periods (the Triassic 
and Jurassic) the usual ferns and tree rushes, but especially 
a new group of trees, called cycads , which somewhat re¬ 
semble the palms. In the third period (the Cretaceous), 
there was an abundance of true palms, besides the sassa¬ 
fras, willow, oak, beech, etc. The animals of the first 
two periods of this age contained the first birds and low 
orders of mammals , or warm-blooded animals. But the 
great feature of the age were the reptiles, which were of 
enormous size and great variety. Many of them (Ichthyo¬ 
saurs and Plesiosaurs) attained a length of over thirty, 
and sometimes as great as seventy, feet. 

There were also species of flying reptiles, with wings 
like bats. One of these (Pterodactyl) had a spread of 
wings of over ten feet. The birds of these two periods 
must also have been of great size, as some of their tracks 
were over two feet long. Some of these birds had long 
tails like reptiles, with the feathers arranged upon each 
side. In the third period (the Cretaceous), there appeared, 
for the first time, fishes related to our modern species, 
similar to the perch and pickerel. 

75. Rocks of the Reptilian Age.— The rocks of 
the first two periods consist principally of sandstones and 
conglomerates, shales and limestones. In many places, the 
sandstones of these periods have been strongly fractured, 
melted rock forced up, and great trap-dikes formed. 


CENOZOIC AGE. 


37 


Large beds of gypsum were also formed during these two 
periods over the interior of the continent. The rocks of 
the third period (the Cretaceous) extend over a large 
region west of the Mississippi. The Cretaceous was the 
great chalk period of Europe, but it was long supposed 
that no true chalk existed upon this continent. Fine 
deposits have, however, been lately discovered in the 
western portions of Kansas. It differs from foreign chalk 
in having no traces of flint. During this period, the cele¬ 
brated green sands of New Jersey were deposited. There 
must have been toward the close of this age a marked 
increase of dry land, especially over the western interior 
of the continent. 


VI. AGE OF MAMMALS, OR CENOZOIC AGE. 

76. —This age receives its name from the great number, 
variety, and enormous size of the mammals (or warm¬ 
blooded animals) which then flourished. It contains two 
periods, the Tertiary and Post-Tertiary. 

77. Life of the Mammalian Age.—The plant life 
of this age includes still more of the same class of plants 
which first made their appearance in the age preceding. 
Many remains are found of the leaves of the hickory, 
maple, mulberry, sycamore, etc., beside those of palms 
and pines. Among the animals of the first, or Tertiary, 
period, there existed many reptiles, such as the crocodile 
and turtle, a shell of one of the latter having been found 
over twelve feet long. Birds were also abundant, not of 
the reptilian kinds, but true birds, much like those found 
to-day. The mammals were even more remarkable. Whales 
lived in great numbers in the ocean. Upon the land, there 
were species of the tapir, as large as a horse; the elephant, 


38 


AGRICULTURAL GEOLOGY. 


camel, horse, deer, wolf, etc., also existed, many of them 
having several species. 

It was in the next or Post-Tertiary period, however, 
that this class of animal life became most remarkable, 
both for the number of the species, and for the size of 
the animals themselves. Among them was the great Irish 
elk, whose height was eleven feet, with the spread of 
the antlers eight feet. The elephant of that period was 
fully one third larger than at the present day, tusks having 
been found over twelve feet long. One of these elephants, 
which was found preserved in the ice in Siberia, had a 
coat of long hair. The mastodon of that period was of 
enormous size; the skeleton of one, found in New York, 
was eleven feet high and seventeen feet long. In South 
America, there was a great sloth, called the megatherium, 
eighteen feet in length; also, an animal similar to the 
modern armadillo, nine feet in length, and covered with 
a great shell. From the very wide distribution of the 
animals of the earlier period, we know that the climate 
over the entire globe must have been much warmer and 
more uniform than we find it to-day. 

78. Rocks of the Mammalian Age.—The deposits 
of the first or Tertiary period in America were not, gen¬ 
erally, solid rock. They consist principally of compacted 
sand, clay, and earth, formed by the action of water, 
very much as such deposits are now made. There were 
also formed some loose coral limestones. A hard, siliceous 
rock, called burr-stone , now used for millstones, belongs 
to this period. The Post-Tertiary period was the great 
soil-forming era of the earth's history. It is divided into 
three epochs: 

(a) The Glacial Epoch —during which, by the action of 
great fields of moving ice, there was a vast transportation 


AGE OF MAN. 


39 


of earthy material from northern to southern latitudes over 
a large extent of the United States. This deposit of 
earth and stones is called drift. It extends over much of 
the Northern States, westward as far as into Kansas and 
Nebraska, and south as far as Southern Ohio and Indiana. 
We shall study fully, in Part II, the action of these gla¬ 
ciers upon the rocks. 

if) Champlain Epoch — during which there were three 
classes of formations going on: ist. Alluvial , formed by 
the waters of rivers, as they bore along earthy material 
in their currents, and distributed it upon their overflow 
beds. 2d. Lacustrme , deposits formed by the action of 
waters of lakes. 3d. Sea Border, similar deposits along 
ocean edges, appearing like elevated beaches. 

(< c ) Terrace Epoch —when, in consequence of the grad¬ 
ual elevation of the earth’s level above the water line, 
the streams cut the alluvial formations into great terraces; 
and the sea border formations were cut into plains of 
different level by the gradually receding waters in the same 
manner. The river terraces along the Connecticut show 
this formation very perfectly. Thus, the first period of 
this age enlarged still further the limits of dry land, while 
the second period brought the surface of the earth into 
proper condition for the coming age of man. 


VII. AGE OF MAN. 

79.—The geological ages of the earth’s history now 
reach their culmination in this, the Age of Man , of which 
our own time is but a continuation. As the events of 
all the preceding ages were plainly but a long prepa¬ 
ration for the present age, so the whole chain of animal 


40 


AGRICULTURAL GEOLOGY. 


creations was finally completed by the appearance of man, 
as the most perfect type of the animal kingdom. 

80. The Life of this Age differs in important re¬ 
spects from that of the ages which preceded it. In some 
classes of animals, especially in birds and insects, our age 
probably excels all others in the number of its species. 
In reptiles and mammals, it falls far behind, and the ocean 
life of this period is much inferior to that of the preceding 
ages. Many species have become extinct, having been 
destroyed by man, and others are fast disappearing through 
the same agency. 

Thus, there existed upon the island of Mauritius until 
the close of the 17th century a huge, clumsy bird, called 
the dodo. Its body was covered with down, and its wings 
were so short and feeble, as to be useless for flight. This 
bird is now utterly extinct. The buffalo once abounded 
over nearly all the plains of the United States; but it is 
now being each year hunted and driven nearer the Rocky 
Mountains, and promises soon to become extinct. 

While there are many evidences to show that man first 
made his appearance upon the earth during the terrace 
epoch of the age of mammals, the exact time of his first 
existence must be regarded as very uncertain, as the dis¬ 
coveries of geologists constantly tend to remove that time 
to a still earlier period of the earth’s history. 

81. Rock Formations of the Age.— Deposits of 
rock material are constantly going on now, as they have 
been in past ages. These deposits are either alluvial , by 
the action of rivers, lacustrine , by that of lakes, or sea 
border , by the ocean. Many of the forces, so powerful 
in the past age, are now in operation. Glaciers are still 
found over many portions of the earth, especially upon 
mountain ranges, crushing and grinding the rocks to earth. 


GEOLOGICAL AGES. 


4i 


The glaciers of the Alps alone number, over six hundred. 
Over many marshes also, deposits of vegetable matter are 
being made in a manner very similar to those of the 
carboniferous age, forming large beds of peat. In some 
of our western States, but especially in Michigan, these 
peat beds are of enormous extent, covering thousands of 
acres, and measuring over thirty feet in depth. Changes of 
level are also constantly taking place in this age. These 
changes are either paroxysmal , as in the case of earth¬ 
quakes, or secular , as in the slow elevation or depression 
of long stretches of coast line in many countries. 

82. Lengths of the Geological Ages. — It is, of 
course, impossible for us to know the absolute length of 
time in each of these ages of the earth’s history. We 
only know that they were immensely long, covering 
periods of time which can hardly be numbered by years— 
periods so long that we can hardly conceive of them. 
Geology simply declares: Time is long. But it is possible 
for us to obtain some idea of the relative lengths of these 
ages. This we can do by comparing the thickness of the 
various rock formations which each age presents. 

If we proceed in this manner, we may divide the strati¬ 
fied rocks of these ages into three eras,—the first, includ¬ 
ing the age of mollusks, age of fishes, and age of coal 
plants; the second, the age of reptiles; and the third, 
the age of mammals. Then, the relative lengths of these 
three eras will be to each other as the numbers 14, 4, 
and 3. That is, the earliest period of the earth’s history, 
when life was of the lowest order, was by far the longest. 
The Age of Man, while it includes within its limits all the 
great events of human history, sinks into utter insignifi¬ 
cance when the absolute length of its time is compared 

with the vast periods which have preceded it. 

A. G.—4 


TABLE OF GEOLOGICAL TIME. 


Cenozoic 

Time. 


Mesozoic 

Time. 


Paleozoic 

Time. 


AGES. PERIODS. EPOCHS. 

Age of Man. 


r 


{ Age 


Alluvial. 
Bluff. 

Post-Tertiary, -j Champlain. 


of Mammals. - 


Tertiary. 


Glacial, or Drift. 
Pliocene. 

Miocene. 

Eocene. 


Cretaceous. 


| Age of Reptiles. . 

1 Jurassic. 

Triassic. 


f Fox Hills Group. 

J Pierre “ 

^ Niobrara “ 

Benton “ 

[ Dakota “ 

[ . Wealden. 

Oolite. 

Lias. 


f New Red Sandst, 
X (Saliferous.) 


Carboniferous. 


f Permian. 
Upper Carb. 


Permo-carbon ifer. 
Upper Coal-meas. 
Lower Coal-meas. 


Lower Carb. 

I 


I Chester limestone, 
j St. Louis “ 

J Warsaw “ 
j Keokuk “ 
j Burlington “ 
l Kinderhook beds. 


Devonian, 
Age of Fishes. 


Silurian, 


U. Sil. 
Era. 


Catskill (Old Red Sandstone). 
Chemung. 

J , Hamilton. 

Corniferous. 

( Oriskany. 

{ Lower Helderberg. 

Sal in a. 

Niagara. 


Age of i j.. Sil. f Trenton. 

Mollusks. I E ra> j Canadian. 

I I Primordial. 


( 42 ) 


Azoic, or Archaean. 










SECTION IV. 


I. THE GEOLOGY OF KANSAS. 


83. —Kansas has an average height of about 2,300 feet 
above the level of the sea. The surface geology of the 
State has been explored by Professors Mudge, Cope, 
Marsh, St. John, and others; and although our knowledge 
is not yet sufficient for us to be able to accurately define 
the outlines of every formation, we yet have a very good 
general idea of their extent. These formations have been 
most perfectly explored by Prof. Mudge, and we shall 
trace them as mapped out by him from the earlier periods 
down to the present, beginning with the eastern boundary 
of the State. 

84. — For our own convenience, we can classify the for¬ 
mations of Kansas as follows: 

AGES. PERIODS. EPOCHS. 


Age of Man. 


Cenozoic Age. 


Post-Tertiary. 



Alluvial. 


Tertiary. 


{ Pliocene. 


( 43 ) 



44 


AGRICULTURAL GEOLOGY. 


AGES. 


PERIODS. 


EPOCHS. 


Mesozoic Age. 


Cretaceous. 


Niobrara. 

Dakota. 


Upper 

Carboniferous. 

Carboniferous Age. < 


Lower 

Carboniferous, 


Permo-carboniferous. 
U. Coal-measures. 

L. Coal-measures. 

Keokuk limestone. 


These come to the surface in different portions of the 
State, because the later formations do not completely cover 
the older ones, but overlap them. Making our starting 
point with the oldest formation, we have : 

85. The Lower Carboniferous. — This covers a 
very small triangular-shaped tract, cut off by the Spring 
River, from the extreme south-east corner of the State. 
It extends six miles on the Indian Territory and ten 
miles along the Missouri line. (See part of the map col¬ 
ored purple.) It is really a continuation into Kansas of 
a similar formation, existing over the adjoining territory in 
Missouri, and is the only part of our State that contains 
metallic deposits of any importance, furnishing ores of zinc 
and lead. Its strata are apparently made up of limestone 
and siliceous material, in the condition of chert, a variety 
of flint. They are in places crowded with fossils, which 
plainly show the identity of the formation with the Keo¬ 
kuk limestone. The strata of this formation have been 
considerably disturbed and thrown out of position. 

86. The Lower Coal Measures. — The productive 
or lower coal measures of this State outcrop at the surface 
over several of the south-eastern counties, the exact limits 
of which area are not as yet clearly defined. According 





COAL MEASURES. 


45 


to Prof. Mudge, its south-eastern border is defined by the 
Spring River, which separates it from the small region of 
the Lower Carboniferous in the extreme south-eastern 
corner of the State. (See the part of the map colored 
green.) 

In this more or less irregular triangular area, several 
distinct coal beds are known to exist, the thickest of 
which is above four feet. In Cherokee and Crawford 
counties, the coal appears at the surface and is easily 
and extensively mined. The bulk of the strata of this 
lower coal formation consists of sandstone, sandy shales, 
and clay shales, with occasional deposits of earthy lime¬ 
stone. 

In connection with some of the coal beds, the shales 
often preserve beautiful specimens of the plants which 
flourished during this epoch, and whose remains were 
finally converted into mineral coal. Also, in some of 
these sandstone deposits are found the remains of gigantic 
club-mosses and equiseta,—plants, whose modern repre¬ 
sentatives, now growing in the soil above these ancient 
and prostrate forests, are, in comparison, very insignificant 
and diminutive. Among animals, a few insects existed, 
and aquatic animals were abundant in the lagoons of the 
ancient forests. But, as we have already learned, these 
coal-forming areas were undergoing alternate submergence 
below water level and elevation above it; and during the 
former condition, when the seas had taken possession of 
the land, they were peopled with a vast variety of marine 
life, whose remains are now so abundant in many of the 
strata forming our coal measures. 

87. Permo-carboniferous and Upper Coal Meas¬ 
ures.— The relations of these two formations in Kansas 
are so intimate, that we shall consider them together. 


46 


AGRICULTURAL GEOLOGY. 


They cover an area of about 20,000 square miles. The 
western boundary of this region may be rudely traced by 
a line starting from the Nebraska border on the north, 
and extending in an irregular south-western course through 
Clay County, and on through the Arkansas valley, crossing 
it in Reno County. All points east of this line, not 
included in the formations of the two preceding periods, 
are Permo-carboniferous and Upper Coal Measures. (See 
the part of the map colored yellow.) The rocks of the 
upper member consist mainly of clay, limy clay or shales, 
limestones, and extensive deposits of gypsum. The lime¬ 
stones afford admirable building material. The Permo- 
carboniferous beds furnish no coal in Kansas. The deposits 
of the Upper Coal Measures are very similar to those of 
the preceding member, with, perhaps, more sandy mate¬ 
rials. They contain few coal veins of sufficient thickness 
for mining, and those which have been reached by boring 
through the strata are at a great depth, and belong to the 
productive or Lower Coal Formation. 

88. The Cretaceous.— The formations of this period 
extend over by far the largest portion of Kansas, covering 
an area of about 41,000 square miles. (See portion of 
the map colored blue.) 

We have already traced the eastern boundary line of 
this period, separating it from the Upper Carboniferous. 
All west of that line belongs to the Cretaceous, except a 
small tract in the north-west corner of the State, which 
would be cut off by a line starting from the Nebraska 
border, in Smith County, and extending irregularly south¬ 
west to the Colorado line, in Wallace County. The rock 
materials of this period are limestones, sandstones, shales, 
and marls, with deposits of genuine chalk. The western 
group of this period (the Niobrara) has furnished collectors 


TER TIAR Y PERIOD. 


47 


with a wonderfal variety of vertebrate fossils — fishes, rep¬ 
tiles, birds, etc. It has not only added a large variety of 
species not known elsewhere, but has also revealed many 
intermediate types of animal life, which have greatly ex¬ 
tended our knowledge of the life-history of the globe. 

89. The Tertiary. —The north-west corner of the State, 
cut off by the line already described, belongs to the Plio¬ 
cene epoch of the Tertiary period. (See the part of the 
map colored red.) The separation between the Cretaceous 
and Tertiary formations, though clearly defined, is hardly 
a sharply traced line, but rather a stretch of country, 
thirty miles wide, extending across the State from Nebraska 
to Colorado. Within this band may be found the forma¬ 
tions of both periods, the Cretaceous, in the low valleys, 
and the Tertiary, upon the high hills. The rocks of the 
Tertiary period are generally crumbling sandstones of 
various colors, overlain with beds of coarse pebbles, etc. 

90. Post-Tertiary. — The formations of the last or 
Post-Tertiary period are much the same in Kansas as else¬ 
where. On the eastern border of the State, along the 
Missouri River, are good specimens of the bluff formation, 
which is identical with that found in similar localities in 
Missouri, Iowa, and Nebraska. It is composed from top 
to bottom of fine earthy material, with little or no coarse 
matter. It is undoubtedly due to the accumulation, just 
after the glacial epoch, of immense deposits of fine sediment 
and silt, before the present channel of the river was cut. 

The alluvial deposits of Kansas are very similar in 
character to those found elsewhere, forming the rich bottom 
lands of our river valleys. Though no marks or scratches 
upon the rock formations of Kansas have yet been found to 
show the action of glaciers during this period, yet accumu¬ 
lations of genuine drift and debris are found throughout 


43 


AGRICULTURAL GEOLOGY. 


the north-eastern portion of the State, where they occupy 
more or less isolated areas, and are evidently the remains 
of a once extensive deposit. Large bowlders of foreign 
rock, or hard-heads , can be seen at many points on both 
sides of the Kansas River, and in various other localities, 
particularly in Pottawatomie County. These bowlders are 
generally a quartzose rock, of a pink or reddish color, and 
are often highly polished. They have probably been trans¬ 
ported from the great Azoic areas of Minnesota and Dakota. 


II. MINERAL RESOURCES OF KANSAS. 

91. Coal. — The coal of Kansas is wholly bituminous, 
or soft coal, and some of its better varieties compare 
favorably with the shaft coal of the eastern coal-producing 
States. It frequently has distributed through it, in seams 
and layers, considerable calc spar, sometimes called tiff 
by miners. This does not injure it for use as a fuel, but 
simply adds useless matter to its weight. Some inferior 
varieties, however, contain quantities of iron pyrites,— 
called fools' gold. When such coal is wet and exposed to 
the air, it frequently takes fire of itself, from the rapid 
oxidation of the pyrites. 

At the present time, there are in this State three prin¬ 
cipal coal mining centers, situated at more or less remote 
points from each other. 1st. In the extreme south-eastern 
portion of the Lower Coal Measure formation, one of the 
principal beds, which outcrops in many localities, is being 
worked both by shallow shafts and by stripping , that is, 
removing the overlying soil and exposing the coal. The 
product of this bed is largely used in smelting the lead 
and zinc ores brought from the neighboring Lower Carbon- 




COAL — LIMESTONE. 


49 


iferous region, and is also sent to all portions of the State. 
2d. At Fort Scott, another and higher coal bed is reached 
by means of shafts, from which large quantities of coal 
are shipped to parts of this State and of Missouri. Much 
of it is colored red by the oxide of iron. 3d. The coal 
mined in Osage County forms a deposit fifteen to thirty 
inches thick; it is of excellent quality, and is distributed 
along the railway lines passing through this district. In 
addition to these areas, also, at Leavenworth a coal bed 
is being worked by a shaft at a depth of between 600 and 
700 feet. At Topeka, a little coal seam, ten to fourteen 
inches thick, is now being mined, the product of which 
is entirely consumed by local demand. 

There are probably many other localities where coal is 
mined to a greater or less extent; but those given are 
sufficient to show the territory from which the principal 
coal supply of the State is obtained. Coal, sometimes 
of fair quality, is found at detached points over the 
Upper Coal Measure area of the State, but rarely in mar¬ 
ketable quantities. In the Dakota group of the Cretaceous 
area, there is found over the north-central portions of the 
State a very inferior variety of coal, called lignite. It is 
obtained by stripping, and answers the purpose of a cheap 
but inferior fuel. 

92. Limestone is found in great quantity, and of 
very superior quality, in nearly every portion of the State, 
except over the area of the Dakota group,, and in the 
extreme north-west. It is found in layers, which are very 
easily worked, and forms the cheapest and handsomest 
building material which the State contains. The purer 
varieties, when burnt in kilns, form a very.superior article 
of quick-lime. At several points in the State, especially 
at Fort Scott, Leavenworth, and Lawrence, the composi- 
a. g.— s 


50 


AGRICULTURAL GEOLOGY. 


tion of the limestone is such that it furnishes, on burning, 
a very excellent grade of hydraulic cement, equal to' the 
best cements found in the market. 

93. Chalk. — Until lately, it has been supposed that 
no true chalk existed in America; but in the last few 
years, immense deposits of a fine, white variety have been 
discovered in the Cretaceous formations of western Kan¬ 
sas, which promise to prove of great value in the manu¬ 
facture of cements. 

94. Sandstone abounds in various localities through¬ 
out the State, especially in the Dakota group of the Cre¬ 
taceous formation, and forms a valuable building material. 

95. Flagging Stone, suitable for pavements, is found 
at various points, but particularly in Osage County, where 
there are extensive quarries. 

96. Gypsum is found abundantly in many portions 
of Kansas. Sometimes it is in beautiful, transparent crys¬ 
tals, when it is called selenite. A very large deposit of 
gypsum extends north of the junction of the Big and 
Little Blue rivers. The product of this bed is ground 
extensively in mills erected for the purpose. 

This valuable mineral is a compound of sulphuric acid, 
lime, and water. When simply ground, it is called plaster , 
and is a very valuable fertilizer. When this plaster is 
heated or boiled , to drive off the water, it forms plaster of 
Paris , and is used for hard finish and stucco work in 
buildings. 

97. Salt. — Salt is almost invariably found associated 
with gypsum, and, as might be expected, the salt resources 
of Kansas are of immense extent; when fully developed, 
it will be a source of great wealth. Salt marshes are 
found at various points throughout the State. In the 
south-western portion, and extending into the Indian Ter- 



METALLIC ORES. 


51 


ritory, is an enormous deposit of fine, white, crystalline 
salt, in some places over two feet thick. It lies upon the 
surface of the ground, and has probably been formed by 
the drying up of an interior salt lake. The salt region 
proper has been defined by Prof. Mudge as covering a 
tract thirty-five by eighty miles in extent, stretching across 
the valleys of the Republican, Solomon, and Saline rivers. 
Through this region, salt springs and marshes are found 
frequently in the midst of a very fertile farming district. 
Salt wells have been sunk at several points by boring. One 
of the most productive of these wells is at Solomon City. 

98. Metallic Ores. — The only portion of Kansas 
that can be considered at all productive in metallic deposits 
is a section in the south-east, in the counties of Linn and 
Cherokee, where the geological formation of western Mis¬ 
souri extends into this State for a short distance. Through 
this region, the common ore of lead, called galena , and 
that of zinc, called black jack , or zinc blende , have been 
mined somewhat extensively; but it is doubtful if with 
any very great profit. The galena, here as nearly every¬ 
where, contains a minute quantity of silver. 

Some of these mines were worked long before the 
settlement of the country, as some suppose, by the Indians, 
but more probably by the early French miners of Missouri. 
On account of the abundance of coal in this region, the 
ores are frequently hauled twelve or fifteen miles from 
beyond the Missouri line, and smelted here with great 
profit. Small deposits of lead and zinc ore are occasionally 
found in other portions of the State in little pockets , but 
never in quantity. 

99. Iron Ore, of the brown hematite variety, is found 
at a few points in the State, and, though of good quality, 
is so small in quantity, as to prove of no importance. 






PART SECOND. 

ORIGIN AND FORMATION OF SOILS. 


(S3) 




* 

















- 









* . • , 9 






















































ORIGIN AND FORMATION OF SOILS. 


SECTION I. 

CONVERSION OF ROCKS INTO SOILS. 

ioo. The Soil, which nearly every-where overlies the 
rock strata of the earth, is of special interest to us all, 
because, in the growth and cultivation of crops, it is the 
only element within our control. The light and heat from 
the sun, and the rain from the clouds, are entirely beyond 
our reach; but we have the power, within certain limits, 
of so controlling and influencing the soil, as to greatly 
increase its fertility. It is very important, then, that we 
should understand fully its origin and composition, and 
the manner in which it has been formed. 

All soil was once solid rock. It has been formed by 
the grinding of these rocks into small fragments, or fine 
dust, by the action of various forces. The finest soil, 
when examined by the microscope, will be found to be 
made up of the little fragments of a great variety of 
rocks and minerals. While the entire mass of the soil, 
taken together, seems of enormous extent, yet when it is 
compared with the mass of the globe itself, it is really 
little more than a slight coating of dust spread over its 
outside surface. 

We shall now study the great forces which have con¬ 
verted the barren rocks into fertile soils. 


( 55 ) 





56 


AGR1CUL TURAL GEOLOG Y 


I. CHANGES OF TEMPERATURE. 

ioi. — (a) We have seen that the earth must once have 
been a melted mass, and that,' in cooling, it became cov¬ 
ered with an outside crust. We have also learned that 
this process of cooling was one of tremendous contraction, 
by which the earth’s surface was thrown up into hills and 
mountain ranges, with wide valleys and low lands between. 
But, besides these general effects, this great force of con¬ 
traction would produce others. The crust of the earth 
would be broken and fractured in many places, and the 
masses of rock, crushed upon each other, would tend to 
grind themselves into small fragments. 

Again, many of the earth’s rocks consisted of crystals 
of different minerals, combined together to form the whole 
rock mass. Now, these crystals would not only expand 
and contract unequally under the change of the tempera¬ 
ture, but each crystal would expand or contract unequally 
in different directions, so that, in these changes, they 
would tend to split off from each other, and into small 
fragments. 

( b) Water in the rocks frequently becomes a most power¬ 
ful force. In freezing, water expands fully one fifteenth 
its bulk, and this force of expansion is so great that 
nothing known is strong enough to resist it. Hence, along 
the base of cliffs and mountains, there are always found 
great piles of rock fragments, split off from the rocks 
above by the force of frost. In the same manner, this 
force acts upon the surface of the rock itself, crumbling 
it into fine dust. If a piece of limestone, for example, be 
wet with water, and exposed to a hard frost over night, 
its surface will be found the next morning, upon exami- 


MOVING WATER. 


57 


nation, to be covered with a minute coating of viud, from 
the particles split off by the frost. The heaving actiop of 
the frost in the winter and spring still further crumbles 
the rock fragments of the soil. 


II. MOVING WATER. 

102.—Water in motion is one of the most powerful 
forces known in converting rocks into soils. By the heat 
of the sun’s rays, water from the ocean, from smaller 
bodies of water, and from the earth itself, is converted 
into an invisible vapor, which rises into the upper regions 
of the air, where it floats and becomes visible as clouds. 
These upper regions are much cooler than the lower air, 
and, hence, these clouds are constantly depositing their 
moisture in the form of rain and snow. Mountains, 
by their effect on the currents of air, act as condensers 
of vapor, and the water gathers rapidly upon them into 
rills and rivulets; these, uniting, form mountain torrents, 
until, finally, we have the great rivers, flowing back to 
the sea. Through its whole course, this moving water 
exerts an immense wearing power upon the rock bed 
beneath. At every point, small particles of solid rock are 
worn away, the little rills cutting their way almost imper¬ 
ceptibly, while the mountain torrents rush down with great 
power, tearing away large rocks in their course. Every 
particle thus removed and those which fall into the cur¬ 
rent from the rocks above add to the wearing power of 
the water. These rock fragments, carried along by the 
current, constantly grind, not only the bed below, but 
also each other to a fine powder. As a result of this 
action, pebbles, brought down by means of water, are 
rounded and polished. Sand frequently becomes so water- 


58 


AGRICULTURAL GEOLOGY. 


worn that its sharp angles are all destroyed, and it becomes 
useless for masonry work. 

The enormous wearing power of water through long 
ages is well shown in the great canons of the Colorado 
River, where gorges have been cut in the solid rock to 
the depth of 6,000 feet, simply by this means. The wear¬ 
ing action of streams is, of course, greatest upon the steep 
inclines of the uplands, where the current is strongest. 
When the stream reaches more level and lower land, its 
motion becomes slower, and the coarse pebbles and gravel 
are dropped upon its bed, while the fine matter, called 
silt , is carried on and generally deposited upon the flood 
ground of the river; that is, where it overflows its banks 
in high water. It is thus that the rich bottom lands of 
our valleys are formed. But in some ca.ses, this fine earth 
is carried still farther on, and is only dropped when the 
river reaches the sea; it then forms a great tract of marshy 
land at the mouth of the river, called a delta. The delta 
of the Mississippi covers over 12,000 square miles, and 
the amount of silt yearly carried down by this river would 
make a bed of soil one mile square and 268 feet deep. 

By the continual wearing away of the rocky uplands, 
and their conversion into fine earth, the continent is be¬ 
coming slowly lowered in height, and its spread-out mate¬ 
rial is extending into the sea. But the wearing action of 
water does not cease when it has reached the ocean. The 
ocean’s waves, currents, and tides are ever wearing away 
the rocks along the coast. This, of course, tends to 
straighten coast lines, by wearing away the headlands, 
and filling up the bays and inlets. Great oceanic currents, 
like the Gulf Stream, doubtless accomplish much of this 
wearing action, although their effects can not be easily 
seen or understood. 


MOVING ICE. 


59 


III. MOVING ICE. 

103.— Ice in motion was at one period of the earth’s 
history an all-important force in converting rocks into soil. 
This force is in action, at the present day, in some places, 
though to a much more limited extent than formerly. 
Glaciers are simply huge mountain rivers, in which the 
water is in the state of ice, and which, instead of flowing 
several miles an hour, rarely move more than a foot a 
day. Glaciers have their origin only upon the summits 
of very high mountains, far up above the region of per¬ 
petual frost, where water can only fall in the form of 
snow. The latter, by its own pressure, becomes converted 
into ice, and the mass of ice and snow finally increases 
to such an extent, that, by its weight, it is forced down 
the mountain’s side through some gorge or valley. It 
then becomes a slowly moving ice river, or glacier, which 
is constantly fed by supplies of ice and snow from the 
regions above. 

The first movement of the glacier, as stated above, is 
due to its own weight and pressure; but as it comes 
down below the line of perpetual snow, its mass becomes 
penetrated in every direction by water, which, as it freezes 
and expands, aids powerfully in forcing it onward. The 
glacier moves most rapidly in its center, its bottom and 
sides being held back by friction against its rocky bed. 
It moves downward, until it reaches a limit where it can 
no longer exist as ice — generally from a half a mile to a 
mile below the snow line—when it gradually melts away, 
and disappears as a river. Ice has the peculiar property, 
when its broken fragments are placed together, of freezing 
into a solid mass. By this property, the glacier is able 


6o 


AGRICULTURAL GEOLOGY. 


to fit itself into the inequalities of its bed, by continually 
crushing and freezing together again. As it moves over 
the ridges and mounds of the valley which forms its bed, 
it often breaks nearly across, forming great cracks, called 
crevasses. From the cliffs above, there are constantly fall¬ 
ing on the surface of the glacier earth, stones, and rocks, 
split off by the action of frost. These substances naturally 
gather near the borders of the glacier, where they form, 
what are called, moraines. 

The main glacier, in its course down the mountain, is 
frequently joined by others; and, as they come together, 
the accumulations upon their inner edges are united into 
a double moraine nearer the center. Thus, by frequent 
additions, the main glacier, towards the lower end, appears 
like a confused mass of earth, rocks, and ice. In its 
progress down the mountain, this glacier, of course, exerts 
an enormous wearing power. Large blocks of rock which 
fall into the crevasses gradually work their way to the 
bottom, by the slow twisting motion of the glacier; there 
they are firmly held by the ice, and, as the glacier slowly 
moves, act as an immense rasp, crushing and scraping the 
rocks beneath into fine powder. 

The course of a glacier can always be traced in any val¬ 
ley, through which it has passed, by the appearance of the 
surfaces of its rocks. The latter are always scratched or 
grooved, sometimes deeply channeled, and again smoothly 
polished, by the grinding action of the bowlders held be¬ 
neath the glacier. The direction of the scratches is always 
the direction of the motion of the glacier. The blocks 
of stone, which have thus been held and ground along, 
beneath the glacier, become worn and rounded bowlders. 
They are finally dropped and' distributed over the country 
by the melting of the ice, and are called hard-heads. 


GLACIAL PERLOD. 


61 

During the course of the glacier, the rock fragments of 
the entire moraine become more or less mixed up with 
the whole mass, and, by their grinding motion upon each 
other, are largely reduced to fine earth. Finally, by the 
slow melting of the extreme lower end of the glacier, the 
whole immense burden is dropped in a great mass of 
bowlders, coarse pebbles, and fine earth. But here, from 
the melting ice, there rises a powerful river, whose waters 
become loaded with rock dust, which is thus carried on 
and distributed through the valley. Many such glaciers 
are in existence and in action at the present day. Those 
of the Alps, around Mt. Blanc, are especially interesting, 
and from many of them flow streams, whose waters are 
so loaded with the rock dust of the glacier that they are 
as white as milk. 

104. The Glacial Period. —As already stated, there 
was once a time in the earth’s history — the Glacial Epoch 
of the Post-Tertiary Period —when a large portion, not 
only of North America, but of Europe, was covered with 
huge glaciers, descending from the north. The evidences 
of this period are very plain. We have already learned 
of the immense deposits of unstratified material, called 
drift , which covers a large part of the United States, 
extending southward to the latitude of the Ohio River, 
and westward into Nebraska and Kansas. This drift con¬ 
sists of fragments of every grade, from fine earth and 
rock dust to bowlders weighing thousands of tons. From 
the great size of the latter, we know that no other natural 
power could have carried them but moving ice. By going 
nearly north, we find the original rock beds, from which 
these bowlders, and much of the drift generally, have 
come. In many cases, they have been carried southward 
over two hundred miles. 


6 2 


AGRICULTURAL GEOLOGY. 


The action of these great glaciers is plainly shown 
on many of the rocks of this region. Where they are 
exposed, they are frequently found covered with grooves 
and scratches, showing the direction and force of the 
glacier; many of the bowlders of the drift are themselves 
grooved and polished. The glaciers of that period were 
of such enormous size, that they could not have been 
confined to the valleys simply; they must have covered 
the entire region — valleys, hills, and mountains. On the 
summits of the last, glacial bowlders have been found, 
and glacial scratches can be seen plainly on the rocks of 
the Green Mountains, 5,000 feet above the sea. It has 
been objected that these great glaciers could not have 
followed the course described, because, from the north pole 
southward, there is no natural slope down which they 
could have moved. But this is really no objection what¬ 
ever; for, as we have already learned, the greatest force 
which drives the glacier forward is not the force of grav¬ 
ity, but the expansive force of freezing water, working in 
the mass of the glacier itself. 

Glaciers have been the great soil formers of the earth’s 
history, crushing and grinding solid rock into fine earth, 
and bringing it into condition to be still further distributed 
by moving water. From an agricultural point of view, 
the work they have performed is very important. They 
have brought together the rock material from a large 
section of country, and have worked it up into earth; 
thus producing a soil composed of many elements, and 
possessing great range of fertility. The soil, thus pro¬ 
duced in each section of country, would necessarily have 
a close connection with the nature of the rock beds north 
of it. Thus we see that the soils of many of our western 
States contain more lime than those of States east, because 


AIR IN MOTION. 63 

the glaciers of this section, in their course, passed over 
limestone formations of great extent 

105. Icebergs.— Ice, in other forms than glaciers, fre¬ 
quently acts as a great carrier of earth and rock material. 
Icebergs are really portions of great northern glaciers — 
frequently those from Greenland — which have extended 
out some distance into the ocean, large masses have then 
been broken off by the action of the waves and carried 
southward by ocean currents. When, on coming into 
warmer latitudes, the ice melts, its immense load of rocks 
and earth is dropped, and forms a great unstratified bank. 
The banks of Newfoundland were thus begun, and are 
each year increasing in size. 

106. Ice of Rivers and Lakes.—When rivers be¬ 
come frozen over in the winter, the rocks and bowlders 
along the shore are frequently frozen in with the ice, and 
are carried off by it in the high water of the next spring. 
They are rapidly ground and worn in their progress, and 
are finally dropped by the melting ice at great distances 
from their previous locations, forming beds of coarse 
gravel and earth. Accumulations of earth and rock mate¬ 
rial are sometimes seen on lake borders at a considerable 
distance from the shore, and were doubtless carried up 
by the ice at a time when the waters covered a greater 
extent of surface than at present. 


IV. WEATHERING ACTION OF WATER AND AIR. 

107. Air in Motion. — The air itself, by its mere force 
of motion and its carrying power, is a great agent in the 
reduction of the rocks to soil. When regular and power¬ 
ful winds pass over sand beds or bars, the sand is caught 


64 


A GRICUL TURAL GE OL O G Y. 


up and whirled onward with much force; and if, in its 
course, it comes in contact with ledges of rock, it acts as 
a sand-blast of great power. Cases are known, in which 
ledges of limestone have become so worn by this action 
of moving sand, that they appear as though they had 
been washed out with water; even much harder rocks are 
rapidly worn away, and quartz becomes brightly polished.. 
Some idea of this power may be gained from the fact, 
that, upon the shores of the ocean, the glass windows of 
houses frequently have minute holes drilled through them 
from the constant wearing action of the sands blown against 
them. By rubbing upon each other while in motion, the 
grains of sand become wind-worn , and as/ thoroughly 
rounded as in water-worn sand. Where sand is thrown up 
on the sea’s beach by the waves, it is frequently carried 
by the wind considerable distances. By this means, small 
bays and harbors are sometimes cut off from the ocean, 
especially at the mouths of rivers, and, in the course of 
time, become entirely filled up, covered with a fertile soil, 
and, finally, with a growth of plants; large tracts of 
valuable land have been formed in this manner. Some¬ 
times, however, the sand becomes so wind-worn and water- 
worn, that it simply drifts and gathers into immense hills, 
called dunes , which are constantly shifting their position. 
These are well seen upon the eastern shore of Lake 
Michigan, where the sand dunes often attain a height of 
from forty to sixty feet, and are very ruinous, sometimes 
covering up houses and entire fields in their course. 

108. Solution.— We have already studied the conver¬ 
sion of rocks into soil by the mechanical effects of water; 
that is, by the action of water in mass . But water pro¬ 
duces other effects of equal importance by its power of 
solution. Even pure water will dissolve many of the ele- 


SOLUTION. 


65 


ments of the rocks in small quantities; and its solvent 
power is greatly increased when the rocks are reduced to 
powder, as the amount of exposed surface is then much 
larger. But pure water is something unknown in nature. 
Water always contains other matters in solution, by which 
its action upon the rocks is greatly increased. The most 
important of these matters, contained in all natural waters, 
is carbonic acid; it is obtained either from the air or from 
the decaying organic matter in the soil. Water will ordi¬ 
narily absorb an amount of carbonic acid equal to its own 
bulk; but at low temperatures, and under great pressure, 
it will take up much more. 

Water, when charged with carbonic acid, is called car¬ 
bonated water , and has a very marked solvent power upon 
many minerals, especially on other carbonates, such as 
limestones, etc. Hence, the waters of all limestone regions 
are called hard, from the quantity of lime they contain. 
Carbonated water also acts upon other minerals much 
more powerfully than pure water. Its action is well shown 
in the waters of mineral wells, which frequently come, 
from a great depth, and contain a great variety of mineral 
matters in solution. We know that these matters are 
largely held dissolved by the carbonic acid contained in 
the water, because, when it is allowed to stand for some 
time exposed to the air, the free carbonic acid escapes, 
and much of the mineral matter settles to the bottom as a 
thick sediment. 

Next in importance of the materials found in much 
natural water, and which greatly increase its destructive 
effects upon the rocks, are the alkalies — aminonia , from 
the air, and potash and soda, from certain minerals of 
the soil. Water, which contains the slightest trace of 
these alkalies, has even a stronger power of dissolving 

A. G. — 6. 


66 


A GRTCUL RURAL GEOLOGY. 


minerals than carbonated waters, and, up to a certain 
point, “its solvent power increases with the amount and 
number of matters dissolved.” Thus, all natural waters 
are constantly exerting their destructive power upon all 
exposed rocks, rapidly hastening their conversion into soil. 
Though this solvent effect may, in any one case, seem to 
be very slight, yet when we remember the immense extent 
to which it has operated through numberless ages, we can 
easily understand the great results it has accomplished. 
Water also operates upon some minerals in another man¬ 
ner, by uniting directly with them, and forming, what are 
called, hydrates. In this condition, they are softer and 
more bulky, and, hence, more easily reduced ♦ to soil. 
Many minerals are so composed that they are directly 
acted on, both by water and by the oxygen of the air, 
and are thus rapidly reduced to powder. 

109. Weathering. — The united action of all these 
forces, air, water, and frost, is called weathering. When 
rocks are exposed to this action, they are more or less 
reduced to soil, according to the nature of the rock, and 
the "extent to which the weathering process has been car¬ 
ried. Quartz rock is the least influenced by weathering of 
any mineral known; for when exposed for long periods 
of time, its surface is but very slightly roughened. Other 
minerals, such as feldspar, are weathered and reduced to 
powder much more easily. Limestone, when pure, will 
withstand the effects of weathering for a great length of 
time; but clayey limestones, and those containing many 
impurities, are rapidly weathered and destroyed. 


PLANT LIFE . 


67 


V. ACTION OF PLANT LIFE. 

no. Plant Life, ever since its appearance upon the 
earth, has exerted a very important influence in the change 
of barren rocks into fertile soil. We may study this action 
of plants under two heads’: 

1 st. The effects produced by living plants themselves. 

2d. The action of decaying vegetable matter. 

in. Effects of Living Plants.—We may suppose 
that, ever since their appearance upon the earth, plants 
have produced the same effects upon the earth’s rocks, as 
we find them producing to-day. This effect is nicely shown 
in the first growth of vegetation upon volcanic rocks. 
When lava flows in a melted condition down the side of 
a volcano, it cools into a hard, barren rock surface. For 
a long time, no plants can live upon it, except little, 
microscopic plants, almost invisible to the naked eye, 
which receive their food wholly from the air. After many 
years, the weathering action of the air will gather a very 
thin film of true soil on the hard surface of the lava, and 
a slightly higher order of plants will begin to appear, 
mosses, lichens, etc., which, as they die, will increase by 
their remains the layer of soil. And so, with each genera¬ 
tion of plants, this change will proceed, until, finally, the 
the sterile rock will become a bed of fruitful soil, capable 
of supporting large trees and of growing farm crops. 
But, in this process of soil forming, the plants have not 
acted simply by contributing their remains to the gathered 
soil, but, with their tiny rootlets, they have attacked the 
solid rock itself, and assisted powerfully in its destruction. 

This action of living plants upon the rocks may be 
owing, first , to the moisture which all growing vegetation 


68 


AGRICUL TURAL GEOL OG Y. 


gathers and holds beneath it, and which is a great aid in 
the formation of soil; and, second , to the action of the 
roots themselves. These are well known to have the power 
of attacking the rock fragments, dissolving and removing 
minute portions. Slabs of limestone are frequently found 
under the soil, with their surfaces covered with a net-work 
of minute grooves or channels, each being the bed of a 
rootlet, which has thus eaten its way into the rock. 
Experiments have been made, by taking pieces of polished 
stone, such as marble, dolomite, etc., placing them in 
vessels under sand, and sowing seeds of grain above. 
The rootlets of the growing plants were seen to descend 
and spread over the stones below; and the latter, when 
examined at the close of the season, were found with 
their surfaces softened and roughened, plainly reduced by 
the action of the rootlets. Even on hard quartz rocks, 
mosses have been found growing so fiimly that they could 
not be removed without scaling off the rock, and beneath 
the surface, the rock was plainly yielding to the plants'* 
action. 

This effect of living plants is, in many cases, probably 
owing to certain organic acids which the roots contain, 
by means of which they are able to dissolve and remove 
a minute portion of the minerals with which they come 
in contact. When these minerals are partly powdered, as 
in the soil, the effects of the plants’ roots are, of course, 
greatly increased with the increased amount of surface 
exposed. Though the matter, thus removed, may seem 
very small in the case of any one plant, yet if we 
consider the effect of the whole mass of plant growth 
which covers the earth, we see that living plants are 
a force of great importance in the conversion of rocks 
into soil. 


VEGE TABLE MA TTER. 


69 


112. Action of Decaying Vegetable Matter.— 

The action of plants on the rocks does not cease with 
their life. When a plant dies, the process of decay be¬ 
gins, and, if freely exposed to the air for a sufficient time, 
nothing will be left but the ash or mineral matter which 
it contains. But it is very rarely that plant decay takes 
place in this manner. The dead remains generally gather 
under the growing plants in a slowly increasing layer, and 
thus, shut off from a free supply of air, the decay goes 
on very slowly, until this mass of vegetable matter be¬ 
comes a black or brown compound, called humus. The 
mold under forest trees, and swamp muck , or peat , are 
good examples of humus; but it exists in nearly every soil. 
This humus assists in the destruction of rocks, and the 
production of soil, for the following reasons: 

1st. Because, in its decaying state, it is constantly absorb¬ 
ing moisture, and keeping all bodies around it damp. 

2d. Its slow decay is constantly producing carbonic 
acid, which is absorbed by the water of the soil, and thus 
acts powerfully upon the rock fragments below. 

3d. Certain organic acids are also produced in decay, 
which act upon the rocks even more rapidly than does 
carbonic acid. 

4th. Finally, with the complete decay of this humus, 
the mineral matter, which existed in the plants which 
formed it, is itself added to the earth from which it was 
taken. 

113. — All these forces, which we have now studied, 
have together converted the sterile rocks of the earth’s 
crust into fruitful soil; and when we consider that they 
have been at work for almost countless ages through the 
various periods of the earth’s history, we see that they 
are abundantly sufficient to account for the layer of soil, 


7 o 


AGRICULTURAL GEOLOGY. 


which nearly every-where covers the earth’s rock strata. 
Nor is the process of soil forming yet completed. All of 
these forces are now in operation in different states of 
activity, and fertile soil is continually forming all around 
us, thus maintaining the earth’s producing power. 


SECTION II. 


CLASSIFICATION OF SOILS. 

114. The Soil, as already defined, is a mixture of 
minute fragments of a great variety of minerals. If we 
examine the soils of any section of country, we find them 
in what appears to be an almost infinite variety; in one 
locality, coarse gravel soils, in another, drifting sands or 
heavy compact clays, or, in still another, rich, dark-colored 
bottom lands , of great fertility and producing power. But, 
endless as this variety of soils appears to be, we shall 
still find that, by careful examination, we can divide them 
all into separate classes, which, though not absolutely 
distinct from each other, will help us much in our study. 
We may classify soils in four different ways: 1st. By their 
formation; 2d. By their composition; 3d. By their phys¬ 
ical properties; 4th. By their position. 


I. BY THEIR FORMATION. 

Soils may be grouped into two classes: 1st. Sedentary 
soils; 2d. Transported soils. 

115. Sedentary Soils are soils which have been 
formed where they are found, and have not been moved 

(70 


72 


AGRICULTURAL GEOLOGY. 


since they were made. They are, of course, quite limited 
in their surface, and are only found in small patches. 
Fair examples of them are found upon the high limestone 
bluffs of Kansas, where the soft limestone rock has crumbled 
upon its surface, thus forming a layer of lime soil. Seden¬ 
tary soils are generally very shallow. They are of no 
great importance, but are quite interesting because we 
know that they must have the same composition as the 
rock which they overlie; and that, by an analysis of the 

rock, we can obtain a very good idea of the general 

nature and value of the soil itself. 

116. Transported Soils are those which have been 
carried or transported to a considerable distance from the 
rock layers from which they were formed. They are of 
three kinds, drift , alluvial , and colluvial soils. 

117. Drift Soils. — These have been formed by the 

action of glaciers, and were brought down during the 

glacial epoch. Glacial drift, as we have already learned, 
consists of a confused mixture of fine earth, pebbles, and 
bowlders, the last sometimes many tons in weight. The 
particles are all much worn and rounded by the action 
of the ice. Drift soils cover a good portion of the north¬ 
ern United States; and the rocks from which they were 
derived may be found in place at a greater or less distance 
north of them. They are among our most valuable and 
fertile soils, as they contain the fine fragments and dust 
from a great variety of rocks. A country covered with 
drift soil may generally be known by the number of 
small round bowlders, called hard-heads , which are found 
through the soil; the surface of the country, also, is fre¬ 
quently quite irregular, being sometimes covered with 
great ridges or banks composed of sand, gravel, and 
bowlders, which are commonly called hogs hacks, and are 


ALLUVIAL SOILS. 


73 


believed to be remains of glacial moraines. Drift soils 
are even now being formed upon a small scale by the 
glaciers of the Alps and of Greenland. 

When, as was usually the case, the drift, on being 
dropped by the melting ice, was still further transported 
by the streams which flowed from the glaciers, the different 
portions which composed it are found in different positions. 
To the north are found the large fragments and bowlders, 
near the place where they were first dropped by the melt¬ 
ing glacier. Further south, will be found in their order 
the gravel, sand, and fine earth, the finest particles being 
carried farthest. Large tracts of sand, found in various 
parts of this country, are known to have been formed 
from drift. 

118. Alluvial Soils are those which have been formed 
by the action of running water, generally over the valleys, 
or bottoms , of streams. These soils, also, are composed 
of fine, rounded particles, often soft and velvety to the 
touch, and, as we might expect, are sometimes found 
more or less stratified. The finer the particles, the longer 
they would be held by running water, and the farther 

they would be carried. Hence, when we examine a 

deposit of alluvial soil, we find the coarse stones and 

bowlders lowest and nearest the source of the stream; the 
finer gravel and sand, next above and still farther down 
the stream; and, lastly, the fine earth and silt, which 

would only be dropped by the water when it began to 
run slowly and evenly. Alluvial soils, such as are found 
over the valleys, or bottom lands, of our large rivers, are 
among the most productive soils known. Sometimes drift 
soil is worked over by streams, and converted into alluvial 
formations. A genuine alluvial soil can be known from 

the fact, that it generally contains rounded pebbles of 
a. g.— 7 . 


74 


AGRICULTURAL GEOLOGY. 


soft rock, which could not exist in drift soils made by 
glaciers. 

119. Colluvial Soils.—These may consist of either 
drift or alluvial matter; but they always contain a quantity 
of sharp, angular rock fragments, showing either that they 
have not been transported far, or else, that they are a 
mixture of sedentary soils with drift or alluvium. 


II. BY THEIR COMPOSITION. 

The great mass of soils may, from their composition, 
be divided into seven general classes, which, from a scien¬ 
tific point of view, are neither distinct nor clearly defined; 
but which answer the purpose of a practical classification. 
By this classification, then, we have gravelly, sandy , clayey , 
loamy , and calcareous soils, marl, and peat. 

120. Gravelly Soils are those containing an abun¬ 
dance of small stones or gravel. The value of a gravelly 
soil depends not only on the general size or coarseness 
of the pebbles, but also upon the nature of the mineral 
which composes them. A pure, coarse, quartz gravel 
would be almost utterly barren and useless. But when 
the gravel pebbles contain other valuable minerals, such 
as feldspar or limestone, we may have produced a soil of 
great fertility. Nearly every gravelly soil contains much 
fine, earthy material, generally of the same nature as the 
coarse pebbles. This finer soil sustains and nourishes the 
crop, while the coarse gravel drains the soil and acts as a 
storer and regulator of the sun’s heat. For this reason, 
many gravelly soils are among the richest and quickest of 
all soils. They are, however, apt to be leachy; that is, 
to have the plant food washed out of them by water. 


LOAMY SOILS. 


75 


121. Sandy Soils. — A soil, to be called sandy, must 
consist of at least ninety per cent of sand. By the word 
sand, we may mean: “Small, granular fragments of rocks, 
no matter of what kind.” Hence, in this class m^y be 
included soils of every grade of value, from the most 
productive to the most utterly worthless; but we commonly 
mean by sand, fine grains of quartz , beds of which, if pure, 
are almost absolutely barren. Sandy soils, however, always 
contain fine fragments of other minerals, so that many of 
them rank very high for their fertility. The famous “green 
sands” of New Jersey contain so much of the mineral, called 
glauconite , that they are largely used upon other soils as a 
fertilizer. 

122. Clayey Soils are those consisting mostly of fine, 
adhesive matter, generally clay. These soils are heavy and 
sticky when wet; are not easily penetrated by water, and 
when dried by the sun, bake and crack. Pure clays are 
for this reason cold , and, generally, poor soils; but, when 
mixed with other materials, they are exceedingly strong 
and durable. Their various colors — yellow, red, brown, 
etc.—are owing to the oxide of iron which they contain. 
Many soils are called clayey, which contain no genuine 
clay at all. They are so called because they have the 
same general heaviness and appearance as clay, though 
they consist of other fine matters. 

123. Loamy Soils embrace all grades of soil between 
clay and sand. They consist of mixtures of both, in various 
proportions. Loamy soils have neither the great heaviness 
or sticky qualities of clay, nor the loose, drifting character 
of sand. They are named heavy clay loams , sandy loams , 
light sandy loams , etc., according to the quantities of sand 
and clay present. Loams make the greater portion of our 
more valuable farming lands. 


7 6 


AGRICULTURAL GEOLOGY. 


124. Calcareous or Lime Soils are those, of which 
carbonate of lime forms a large proportion. They are 
known from the fact that, when any acid, such as vinegar, 
is poured over them, they bubble violently from the escape 
of carbonic acid. Many Kansas soils contain enough lime 
to be properly called calcareous soils. When mixed with 
other materials, these soils are called calcareous sands, clays, 
or loams, according to the nature of the material. 

125. Marls are mixtures, in about equal parts, of 
finely divided clay and carbonate of lime. Shell marl is 
nearly pure carbonate of lime, often found at the bottom 
of swamps. 

126. Peat is partially decayed vegetable matter, pro¬ 
duced by the slow decay of plants and their remains un¬ 
der water. Peaty soils are those containing much of this 
half-decayed vegetable matter. Soils produced by the 
decay of plant-remains not under water, are called vegetable 
molds. The mold under forest trees, formed of fallen 
leaves, twigs, etc., is the best illustration of this class. 


III. BY THEIR PHYSICAL PROPERTIES. 


127. Again, soils may be divided into heavy and light 
soils; but, as these words are not here used in their ordi¬ 
nary sense, this division requires some explanation. By 
heavy soils are meant, not those which have great weight, 
but those which are so compact in their structure that they 
strongly resist the movement of the plow through them, 
and hence are hard and heavy to cultivate. And, on the 
other hand, by light soils are meant those which are so 
light and porous in their texture that they can be lightly 
and easily cultivated. 


SPECIFIC GRAVITY OF SOILS. 


77 


128. Absolute Weight of Soils. — Soils vary much 
in their absolute weight, and many which in this sense 
may be heavy are really light soils to the farmer; and, on 
the other hand, many soils which are light in their actual 
weight are heavy soils to the farmer. For example, dry 
sand weighs no pounds to the cubic foot; ordinary soil, 
90 pounds; heavy clay, 75 pounds; and peat soils, from 30 
to 50 pounds to the cubic foot. Sandy soils, however, as 
we all know, are in the farmer’s sense of the word the 
lightest of all soils, because they are easiest to work, while 
in actual weight they are the heaviest soils known. Clay, 
also, which we call a heavy soil , because hard and unyield¬ 
ing to the plow, is really a light soil in actual weight. 
Peat soils are light in both senses of the word, having 
little actual weight, and being loose and porous. 

129. Specific Gravity of Soils. — By this we mean 
their relative weight as compared with an equal bulk of 
water. The specific gravity of all soils is nearly the same. 
A cubic foot of water weighs 62^ pounds. Upon com¬ 
paring with this a solid cubic foot each of a great variety 
of soils, from which all the air had been driven, we would 
find their average weight to be 165.62 -{- pounds, and 
hence their average relative weight or specific gravity is 
2.65. In this experiment we must, of course, weigh simply 
the solid soil. If we should take the soil in its ordi¬ 
nary porous condition, containing much air, we should of 
course get a much smaller number, which would not be 
its true specific gravity. The mechanical condition of the 
soil has much to do with its fertility. Up to a certain 
point, the more finely divided, the greater will be its fer¬ 
tility, because every part can be easily penetrated by the 
plant’s roots. But this fine condition can be carried too 
far, and the soil may become so finely divided that, when 


73 


AGRICULTURAL GEOLOGY. 


wet, its particles will stick together in a hard, compact 
mass, which can not be penetrated by the growing roots. 
It then becomes, in the farmer’s sense, a heavy soil. 

IV. BY THEIR POSITION. 

Under this head soils are commonly divided into three 
classes —surface soil , subsoil , and hard-pan. 

130. Surface Soil. — By the surface soil is meant that 
portion ordinarily stirred by the plow, and penetrated by 
the rain and the roots of the growing crops. It is generally 
of a dark color, because it contains more or less organic 
matter from decaying rootlets, etc. This layer is some¬ 
times called the active soil or tilth. 

131 Sub Soil. — By the subsoil is meant that soil 
layer immediately beneath the surface or active soil. It is 
generally more compact, less stirred in cultivation, and 
sometimes of a different color. Biit in long cultivated 
soils, the surface soil shades so gradually into the sub¬ 
soil that it is sometimes impossible to draw a line telling 
where one begins and the other leaves off. In other 
cases, the division between the two can be clearly traced 
by the eye. 

132. Hard-Pan. —This is the hard, compact layer, 
wholly beneath the subsoil. In the condition of hard- 
pan, the soil is really returning again to the condition 
of rock — the fine particles of soil, packed into a com¬ 
pact mass, are being slowly cemented together by the 
solutions of mineral matters brought down by the water of 
the soil, so that, if undisturbed, the hard-pan will become 
solid rock. When this layer is at the bottom of a swamp 
or marsh, it is called moor-bed pan. 


SECTION III. 


THE FARM SOILS OF KANSAS. 

133. The general surface of Kansas is a rolling 
prairie; but it is an undoubted fact that the prairie sur¬ 
face is slowly decreasing, while the timbered areas are 
slowly increasing in extent. This is owing, both to the 
planting of trees by settlers and to the constant decrease 
of prairie fires. The farm-soils of Kansas, while in many 
respects similar to those of the surrounding states, yet 
present some distinct and peculiar features. The soil of 
this region was probably, in part at least, of drift origin, 
but this has since been very greatly changed in its char¬ 
acter by the action of water, so that little of its true drift- 
nature remains. As we have already learned, the bowl¬ 
ders or hard-heads of the glacial drift are only found in 
comparatively small numbers, scattered over the north¬ 
eastern portions of the State. 

134. Bluff- Soil. —The soil of the Bluff formation oc¬ 
cupies the eastern portion of the State, along the Missouri 
river, and is very marked and peculiar in its nature. It has 
been formed later than the drift, is frequently of great depth, 
and through its entire mass is composed of fine earthy 
matter, with little or no gravel or stones. It is probably 
the accumulated sediment of the river, formed immediately 

(79) 


8o 


A GRICUL TURA L GE OLOGY. 


at the close of the glacial epoch, before the present chan¬ 
nel was cut. Soil of the same kind is found in exactly 
similar position in Iowa, Nebraska, and Missouri. But the 
great mass of the soils of the State may be divided into 
three general classes — low bottom , second bottom , and high 
prairie. 

135. Low Bottom. —In this class are included the 
exceedingly rich alluvial soils occupying the low, flat val¬ 
ley beds of our rivers, but a few feet above water level. 
They have been formed from the accumulated material 
brought down by the rivers in flood seasons, and dropped 
by the gradually subsiding waters. They are soils of great 
depth — frequently over 25 feet by actual measurement — 
and probably constitute the most valuable farming lands of 
the State. The soil is a rich, dark loam, sometimes almost 
black from the great abundance of organic matter. This 
soil has great capacity for resisting the injurious effects of 
drought. 

136. Second Bottom. — The soils of this class in¬ 
clude the large areas of farming lands extending along the 
next terrace above the low bottoms. They were formed 
in the same manner as the latter, but at an earlier period, 
when the rivers covered a much broader and deeper bed 
than at present. The second bottom soils probably make 
up the greater part of the first-class farming lands of our 
State; they are scarcely less inferior to the preceding class 
in fertility, though a trifle less rich in organic matter. 

137. High Prairie. — This class includes the high 
rolling uplands of the State, covering much of its central 
and western portions. The soils of Kansas are largely of 
this class, and are probably in great part of local origin. 
They have their origin in the reduction of the rocks of 
carboniferous and cretaceous formations of the State. The 


KANSAS SOILS. 


8 l 


undulation of the strata of these formations in Kansas is 
such that their edges have been exposed to the weathering 
action of the atmosphere, frost, water, etc.; by this means 
they have become crumbled, and their fine material has 
been intermixed, and strewn over the uplands and slopes, 
where we find it compacted into soils, sometimes of great 
depth. Generally it will be found, in any locality, that the 
upland soil has, as the basis of its composition, the same 
materials as the rock strata of the neighborhood. 

The comparison of these local soils with the rock strata 
from which they have been derived, will always be found 
a very interesting study. 

A good illustration of this connection is shown in the 
vicinity of St. George, in Pottawatomie County, where 
there exists quite an extensive tract of sandy soil. This 
must plainly be referred to the extensive deposits of Upper 
Coal Measure sandstone and sandy shales, known to be the 
immediately underlying rocks of this locality; for as we 
ascend to the higher grounds, with their overlying lime¬ 
stone, clay, and marly deposits, we are at once impressed 
by the marked change in the character of the .surface soil. 
Similar striking illustrations of the derivation of local soils 
from the immediately underlying rock strata are shown at 
many points on the slopes bordering the valley of the 
Kansas River, as well as in other portions of the State. 

138. Special characteristics of Kansas Soils.— 
The soils of Kansas, in general, are well known as among 
the most fertile and productive in the United States; and 
are specially remarkable for two reasons: 1st. Their power 
of resisting the ruinous effects of excessive drought. 2d. 
Their great fertility under continued and exhaustive crop¬ 
ping, without the use of fertilizers. The first characteristic 
is every-where noticed by the most careless observer. Not 


82 


AGRICULTURAL GEOLOGY. 


only does the capacity of the soil for moisture seem almost 
infinite, but its retaining power is equally great. This 
valuable property is probably owing to the large amount 
of organic matter present in all our soils, giving them 
their rich, dark character. Frequently, after a heavy 
shower, the soil will be found moist only to the depth of 
an inch or two; and only after prolonged storms will it 
be found sensibly wet to any great depth. These soils dry 
quite as slowly as they become wet; and, after weeks of 
dry weather, the surface, when brushed away for an inch 
in depth, will be found underlain by dark, damp earth. 
Hence, the long periods of excessively dry weather which 
occur in many growing seasons, and which would otherwise 
prove very disastrous, are here met by the large stores of 
moisture, slowly carried up to the rootlets of the growing 
crops, which are thus kept fresh and luxuriant. 

The second characteristic of Kansas soils is equally a 
matter of common observation. Perhaps in no region 
have heavy and exhausting crops been grown continuously 
with so little care, either in cultivation or in the use of 
fertilizers; and yet in very few localities is the fertility of 
the soil sensibly reduced. Careful culture and the use of 
fertilizers is almost invariably followed by as heavy crops 
as are known ever to have been grown. 


Note.— A chemical analysis of the soil, while it proves nothing 
of itself, is frequently very interesting. The analyses which have 
been made of numerous Kansas soils, by the writer, show, among 
many other interesting things, the presence of a great quantity of 
organic matter, which, in rich soils from the center of the State, 
frequently amounts to over ten per cent of the entire weight of 
the soil. 


SECTION IV. 


RELATION OF SOILS TO CROPS. 

139. There is probably no subject in connection with 
the origin and formation of soils which is less understood, 
or concerning which there are more false impressions, than 
that of the relations which exist between soils and the 
crops to be grown upon them. We shall study only the 
more important of these relations here. 

140. Fertility of Soils. — By a fertile soil we com¬ 
monly mean one which, in an average season and with 
ordinary cultivation, will produce an average standard crop, 
such as wheat, corn, rye, etc.; but it is plain that this fer¬ 
tility of the soil is only relative, and depends upon many 
other circumstances than the simple presence of the ele¬ 
ments of plant food in the soil. 

141. Influence of Climate. — Climate, above all other 
circumstances, determines a soils fertility. There are very 
few soils which are barren or unproductive from the mere 
absence of the elements of plant food; but there are large 
tracts upon the earth’s surface which are no better than 
deserts, not because the soil is sterile, but because the con¬ 
ditions of climate — such as lack of rain, excessive cold in 
winter, or heat in summer — are unfavorable to the growth 
of vegetation. In like manner, a soil which in a favorable 

183 ) 


8 4 


A GRICUL TURA L GEO LOG Y. 


season is very fertile and produces an abundant crop, may, 
in a season of drought, prove utterly barren and unproduc¬ 
tive. On the other hand, a soil which is naturally light 
and poor, may, in an unusually favorable season, yield a 
thrifty crop. 

There are other physical circumstances, also — such as 
standing water, poor natural drainage, etc. — frequently ex¬ 
isting in compact heavy soils which may render a tract of 
land naturally fertile almost useless for cultivation. 

142. Special Crops. — Among farmers, fruit-growers, 
and practical men generally, there is a very wide belief 
that for each particular crop there is also a particular kind 
of soil best adapted to its growth and cultivation. There 
are many facts in our general experience which would seem 
to support such a theory. For example, we all know that 
wheat generally does best on a high, open, lime soil; 
among fruits, pears are safest on a heavy clay soil; grapes, 
upon an open gravel or a loamy soil; while certain other 
crops prove most productive on warm, sandy soils. The 
explanation of all this is probably to be found not so 
much in the different composition of these various soils, as 
in their different physical peculiarities, such as warmth, 
moisture, drainage, etc., which seem to particularly adapt 
them to the crops in question. Out of this general expe¬ 
rience above mentioned, there has grown another popular 
theory, which contains little truth, and has but few facts 
to sustain it, viz., that by analyzing a soil — that is, finding 
out the elements which compose it — it is possible to tell 
what particular kind of crop it is best adapted to produce. 

This theory, which is now generally regarded by scien¬ 
tific men as untrue, has grown out of simple theorizing, 
in a manner which we may briefly explain as follows: If 
we burn a plant, we have left a dry powder which we call 


ANALYSIS OF TIIE SOIL. 


85 


its ash; this ash represents that portion of the plant’s 
food which it has taken from the soil, and is absolutely 
necessary to its growth. Now it has been argued that if 
we could find out, by analysis, the elements which com¬ 
pose this ash of the plant, we should at once know what 
elements the soil must contain to grow it; and that, if 
these proved to be wanting in the soil, we could add them 
in their proper proportions as fertilizers. This theory, when 
put in practice, is found to fail utterly, because it takes no 
account of another element of the plant’s food, called the 
nitrogenous element, because it furnishes nitrogen to the 
plant. This is fully as important as the plant’s ash-food, 
and without it no crops could be grown. It is impossible 
for us to tell from the analysis of a soil what crops will be 
specially adapted to it, as it is probable that, with very few 
exceptions, all fertile soils contain, in greater or less quan¬ 
tity, the mineral elements necessary for the growth of all 
standard crops. Whether these can be grown upon them 
profitably or not will depend upon their physical condition, 
the nature of climate, method of culture, etc. 

143. Chemical Analysis of the Soil. — From the 
last paragraph we conclude that, although by a chemical 
analysis of a soil we are able to find the exact number 
and proportion of all its elements, yet this will not of 
itself tell us any thing as to its fertility, or the crops which 
it will best grow. The reason of this is plain, when we 
know the condition in which the minerals composing the 
soil exist. The mineral elements of the soil are of three 
kinds: 

1st. The mechanical basis of the soil, which simply serves 
to hold the plant, and which gives little or nothing to its 
growth. For example, sand. 

2d. The minute mineral particles, which, under the weath- 


86 


AGRICULTURAL GEOLOGY. 


ering action of the air and water, are rapidly being pow¬ 
dered and becoming plant-food. 

$d. The immediately soluble and available mineral food 
of the plant, which is ready to be at once dissolved and 
taken up by the plant’s roots. 

The present fertility or barrenness of a soil must of 
course depend upon the amount of the third class present; 
but it is not possible for chemical analysis to tell us accu¬ 
rately what part of the mineral elements of the soil is in 
a condition to be at once useful to the plant, and what is 
of no value, or only very slowly becoming plant food. 
The only possible way for us to know absolutely a soil’s 
producing power is to measure the crop which it will 
grow. Still, a chemical analysis of the soil is always in¬ 
teresting, and there are cases in which it may prove valu¬ 
able. Whenever a soil is found to be barren, from the 
entire want of any part of the plant’s food, or from the 
presence of any poisonous compound, a chemical analysis 
will always point out to us the cause of the trouble, and 
the remedy. 

144. Mechanical Analysis of the Soil.— For prac¬ 
tical uses a mechanical analysis of the soil will give us a 
very good idea of its general condition. This can easily 
be performed as follows: A portion of the soil may be 
weighed and passed through a moderately coarse sieve; 
that which can not be passed through may then be weighed 
separately, and called gravel and coarse sand. The part 
which passes through the sieve should be placed in a vessel 
of water, stirred rapidly, and allowed to settle for a few 
moments. That which settles to the bottom may be dried, 
weighed, and called fine earth. In the water above the 
fine earth will be found a quantity of exceedingly fine 
matter, held suspended by the water. To separate this, 


PREPARATION OF SOILS. 


87 


the water may be passed through a filter-cone, made of 
white, unsized paper, and the matter which collects upon 
it may be dried, weighed, and called impalpable matter. 

The value of such an analysis depends upon the fact 
that, other things being equal, the finer the particles of a 
soil are divided, the greater will be its fertility. In several 
soils, of nearly the same composition, the one having the 
greatest quantity of fine matter will carry the heaviest crops. 

Regions which have long been celebrated for their en¬ 
ormous crops, will almost invariably be found to be those 
having a very finely divided soil. This would be very 
naturally the case, because a finely divided soil offers a 
much greater surface to the weathering action of the air 
and water, so that more plant food becomes soluble; and, 
at the same time, the little rootlets of the plants themselves 
can spread far more freely and absorb this extra supply 
of plant food. Of course it is possible, as in a heavy clay 
soil, to have this division of the soil particles carried so 
far that all these good results will be lost, and a solid, 
compact water-tight soil may be the consequence. 

145. Preparation of Soils for Crops. — The ordi¬ 
nary practices of the farmer in preparing his fields for 
crops, although followed for centuries simply because they 
have been found to give us the best results, can yet all be 
explained upon scientific principles. Such simple operations 
as plowing and harrowing have for their first great object 
the pulverization of the soil. By these means we obtain : 

1 st. A free movement of the little rootlets of the young 
plant through the soil. 

2 d. A clear passage for the water of the soil, so that 
after rains it will be rapidly absorbed, and, during dry 
weather, easily carried up to the plant from the damp 
earth below. 


88 


AGRICULTURAL GEOLOGY. 


$d. The free presence of air in the soil, absolutely neces¬ 
sary to the growth of the plant. 

4 th. An abundant supply of mineral food, which is fur¬ 
nished the plant by the process of weathering, constantly 
going on in an open soil. 

The process of cultivation, during the growing season, 
carries on all these operations still more perfectly. By fall 
plowing we call to our aid the powerful action of frost, 
during the winter, upon the hard minerals of the soil. 
This action of frost is so strong, that, during a single 
winter, it will produce, upon an exposed soil, fully one 
third the effects of plowing. 

146. Fallowing. — The operation of fallowing is gen¬ 
erally made upon old or worn out soils, and is simply the 
process of weathering upon a large scale; that is, the soil 
is plowed and exposed,* in a naked condition, to the action 
of air, water, frost, etc., for one or more seasons. By this 
means the soluble parts of the plant’s food, which had be¬ 
come exhausted, are again restored by the weathering of 
other mineral particles, and the soil is then ready for an¬ 
other crop. 

147. — From what we have already learned of the influ¬ 
ence of climate, and the physical conditions of a soil, upon 
its fertility, it is evident that no fixed rule as to the method 
of preparing the soil, for any particular crop, can be laid 
down as suitable to all localities. Many methods which 
are employed, with great success, in the Eastern States, 
fail entirely when used in the growth of Kansas crops. In 
every case the nature of the soil and of the crop, the gen¬ 
eral character of the climate, and the peculiarities of the 
season, must all be taken into consideration in determining 
the method which can be followed with the best hope of 


success. 


SECTION V. 


EXHAUSTION OF SOILS. 


148. —The question of the exhaustion of soils has always 
produced much dispute and discussion, and, even at the 
present day, there can hardly be said to be any uniform 
opinion upon the subject. By some it is maintained that 
the exhaustion of our soils is a danger against which 
farmers must constantly guard themselves; while others 
believe that such a danger is wholly imaginary, and never 
occurs in actual practice. There are certain facts, how¬ 
ever, which can not be questioned, and which have been 
observed by every cultivator. 

149. Worn-out Soils. — It is well known that when 
any heavy crop is grown, for years in succession, upon a 
piece of land, without the use of fertilizers, the yield will 
each year become less and less, until finally it will be so 
small as hardly to return to the farmer the seed itself. 
Such an experience is not uncommon where corn and 
wheat are grown for a long period of years without fer¬ 
tilizers. Other crops, which are more exhausting in their 
effects upon the soil, produce these results more completely 
even than the grain crops. The tobacco plant is one of 
the most notable in this respect; and the worn-out tobacco 
fields in portions of the Southern States, especially in Vir- 

a G.— s (89) 


9° 


A GRICUL TURA L GEOLOGY. 


ginia, are well-known examples of its effects after long 
continued cropping, upon the same soil. 

If we would seek an explanation of these effects, it is 
plain that we must look for them in the plant-food taken 
from the soil. This we know to be of two kinds: first, 
the mineral food, or what we call the plant’s ash; second, 
its nitrogenous food, furnished largely by the decaying or¬ 
ganic matter of the soil. Of these two classes of plant 
food, the latter is, probably, the more rapidly exhausted by 
the continuous growth of the same crop, but the plant’s 
mineral food is also exhausted by it. 

These facts are well shown in an estimate made by Pro¬ 
fessor Johnson, upon the hay crop, as follows: A hay crop 
probably carries off more mineral matter than any other 
known; thus, one crop of hay, of two and a half tons, 
will remove 400 pounds of mineral matter from each acre 
of the soil. When we compare this with the whole weight 
of the soil, about 4,000,000 pounds to the acre, to the 
depth of twelve inches, 4 :he quantity seems very small. 
But when we remember, that out of one hundred parts of 
this soil, not more than one part gives food directly to the 
plant, we see that the number of hay crops which a soil 
can produce is by no means unlimited. The same might 
be shown of the other staple crops of the farm. We can, 
therefore, readily understand, how, by continued cropping 
for long periods of years, without the return of any equiv¬ 
alent in the form of fertilizers, we may easily reduce the 
producing power of our farms to a very low point. 

150. Theoretical Exhaustion. — Taking these well- 
known facts as a basis, many writers have attempted to 
prove, that a system of farming which does not return to 
the soil, in the form of fertilizers, whatever is taken from 
it in the form of crops, would finally produce such an 


PR A CTICA L EXHA US TION. 


9 1 


exhaustion of the soil that it would sustain no plant growth 
whatever. But such absolute exhaustion is impossible, 
and, as Professor Johnson says, “exists only in the im¬ 
agination.” A soil, once fertile, could never be reduced 
to utter barrenness simply by cropping. 

151. Practical Exhaustion. — While complete ex¬ 
haustion of the soil, so that it will sustain no plant-life, is 
impossible, yet it is very easy to bring about a practical 
exhaustion, by careless culture. This is the case, to use 
the language of Prof. Johnson, “ when the cost of crop¬ 
ping is greater than the value of the crop grown.” Hence, 
no soil can be called productive which does not produce 
a crop whose value is more than sufficient to cover the 
time, labor, and money consumed in raising it. Whenever 
the value of the crop is too small to cover this expense, 
the soil is practically exhausted, and further cultivation of 
it is unprofitable. 

From this it will be seen that there are many other ele¬ 
ments, which are very important in the exhaustion of soils, 
besides the simple quantity of the crop produced: such are, 
the market value of the crop, distance from the market, 
cost of transportation, etc. Let us suppose, for example, 
that we have two equally fertile fields, one in Kansas, and 
the other near New York City. Without taking into con¬ 
sideration the value of the land, it is plain that, with ex¬ 
actly the same system of cropping, the Kansas field would 
become practically exhausted first, because the value of the 
crop is much less in Kansas than in New York, and the 
cost of transporting it to its final market much greater. 

When a soil has become practically exhausted, it is very 

easy to restore it again, to its first fertility, by proper 

treatment. It has become exhausted because its present 

available plant-food has been nearly consumed. The proper 


92 


AGRICUL1 'URAL GEOLOGY. 


plant-food may be restored either by the use of fertilizers, 
or by letting it lie fallow for a number of seasons, so that 
its reserve matter may be made available in this capacity 
by the weathering action of the atmosphere. 

152. First-class Farming. — No process of farm- 
culture can be regarded as first class which does not aim 
to accomplish these two things: 

1st. To so change or rotate the staple farm crops that 
no field shall become exhausted, to any extent, of any one 
kind of plant-food. 

2 d. To preserve the fertility of the soil at a fixed high 
standard by returning to the soil, as far as possible, a full 
equivalent for every crop which has been taken from its 
surface. 


INDEX 



Page 



Page 

Age, Azoic .... 

2 9 

Cberokee County, Coal Beds of 


45 

“ of Mollusks— Silurian 

29 

Chert. 


44 

“ of Fishes — Devonian . 

32 

Clay. 


17 

“ of Coal Plants — Carboniferous 33 

Clayey Soils .... 


75 

“ of Reptiles—Mesozoic 

36 

Clay Slate . . . , 


20 

“ of Mammals — Cenozoic 

37 

Climate, Influence on Fertility 


83 

“ of Man .... 

39 

Coal, Formation of 


34 

Ages, Geological . 

. 27,28 

“ Varieties of . 


35 

“ “ Lengths of 

41 

“ of Kansas 


48,49 

Air in motion, wearing power 

63 

Colluvial Soils 


74 

Albite. 

17 

Conformable Strata 


25 

Alkalies . 

. 16 

Conglomerates 


21 

“ Solvent action of 

65 

Connecticut River Terraces 


39 

Alluvial Formations 

39 

Coral Reefs .... 


26 

“ Soils 

73 

Corniferous Formation 


33 

Aluminum .... 

. 16 

Cretaceous Period 


36 

Analysis, Chemical, of Soils 

• 85 

“ “ in Kansas 


46 

“ Mechanical, of Soils 

86 

Crevasses .... 


60 

Anthracite Coal 

35 

Crops, Preparation of Soils for 


87,88 

Asbestos .... 

T 7 

Special 


84 

Ash of Plants 

. 85,90 

Crystalline Rocks . 


20 



Crystals. 


15 

Birds in Cenozoic Time 

37 

Cycads. 


36 

“ “ Mesozoic Time 

36 




Bituminous Coal 

35 

Deer — Cenozoic . 


38 

Bluff Soil in Kansas 

79 

Delta of Mississippi 


58 

Bottom Lands 

73 

Devonian Age, Life of . 


32 

Buffalo, Extinction of . 

40 

“ “ Rocks of . 


32,33 

Burr Stone .... 

• 38 

Dikes . 


24 



Dip. 


25 

Calcareous Soils 

76 

Dodo, Extinction of 


40 

Calcite. 

18 

Dolomite .... 


18,21 

Cannel Coal .... 

35 

Drift. 


39 . 6 i 

Canons of Colorado 

• 58 

“ in Kansas 


47 

Carbon and Carbonates 

. 18 

“ Soils .... 


72,73 

Carbonic Acid, Solvent Power 

65 ! 

Dunes. 


64 

Carboniferous Age, Life of . 

33 

• 



“ “ Rocks of 

• 34 ! 

Earth’s Crust, Contraction of 


12 

Catskill Formation 

33 

“ Interior 


11,12 

Chalk in Cretaceous Period 

37 

Earth, Structure of the 


n 

“ “ Kansas 

50 

Elements .... 


15 

Champlain Epoch . 

39 

Elephant — Cenozoic 


37 

Chemung Formation 

33 

Elk, Irish . . . 


38 


( 93 ) 














94 


INDEX. 


I 




Page 



Page 

Epoch .... 

• 

29 

Hay Crop, Exhaustive Effects 


90 

Everest Mt., Height of 

. . 

12 

High Prairie Soils 


80 

Exhausted Soils, Restoration of . 

9 r 

Hogs Backs . . „ 


72 

Exhaustion of Soils 

. , 

89 

Hornblende .... 


U 

“ “ “ Practical 

9 1 

Horse — Cenozoic 


38 

“ “ “ Theoretical . 

90 

Humus. 


69 

Extinction of Species . 

• 

40 

Hydrates 


66 

Fallowing 


88, 92 

Icebergs .... 


63 

Farming, First-class 

. • 

92 

Ice, of Rivers and Lakes 


63 

Fault .... 

• 

25 

Ichthyosaurus 


36 

Feldspar 

• 


Igneous Rocks 


19 

Fertility of Soils 

. 

83,86 

Insects — Devonian 


3 2 

Fertility of Soils, Effect of Fine 


Interior Rock Crust 


14 

Division on 

• • 

87 

Irish Elk .... 


38 

Fishes — Devonian 

• • 

3 2 

Iron Ore in Azoic Time 


29 

“ Mesozoic 

• 

36 

“ “ Kansas 


5i 

Flagging Stone of Kansas 

• 

50 

“ Rust .... 


16 

Flood-ground of Rivers 

• . 

58 




Formations 

• • 

22,23 

Jurassic Period 


36 

Fort Scott Coal Seam 

• , 

49 




Fossils .... 

• . 

28 

Kansas, Bluff Soil 


79 

Fragmental Rocks 

• • 

21 

“ Bottom Soils 


80 

Frost, Force of 

• . 

56,88 

“ Chalk 


50 




“ Coal Fields 


48 

Galena in Kansas . 

. . 

5i 

“ Cretaceous Formations 


46 

Glacial Accumulations in Kansas 

47 

“ Flagging Stone 


50 

“ Epoch 

. . 

38, 61 

“ Glacial Indications in 


47 

Glaciers as Soil Formers 

. . 

62 

“ Gypsum . 


5o 

“ in Age of Man 

. 

40 

“ High Prairie 


80 

“ Motion of 

. . 

59. 62 

“ Limestone 


49 

“ of the Alps 

• • 

61 

“ Lower Carboniferous 

of 

44 

“ Wearing power of 

. 

60 

“ “ Coal Measures 

of 

44 

Glauconite . • 

. 

75 

“ Metallic Deposits of 


5i 

Granite .... 

• , 

20 

“ Permo-carboniferous of . 

45 

“ Originally a Stratified Rock 24 

" Post-Tertiary of 


47 

Granular Marble . 

• . 

21 

“ Salt .... 


50 

Gravelly Soils 

. 

74 

“ Sandstone 


50 

Green Mountains, First Appearance 31 

“ Soils .... 


79 

Green Mountains, Glacial 

Bowl- 


“ “ Peculiarities of 


81 

ders on ... 

• • 

62 

“ Surface of 


43 

Green Sands . 

) • 

37 

“ Table of Formations of . 

43, 44 

Gulf Stream, Wearing Power 

58 

“ Tertiary of 


47 

Gypsum . . . . 

• • 

19 

“ Upper Coal Measures 

of 

45 

“ of Kansas 

• 

50 

Kaolinite .... 


1 7 

Hamilton Formation 

• • 

33 

Lacustrine Formation . . 


39 

Hard-heads 

• • 

60,72 

Laminated Structure 


23 

“ in Kansas 

• • 

48 

Lava ..... 


21 

Hard-pan 

• • 

78 

“ First Growth of Plants on 

• 

67 

















INDEX. 


95 





Page 



Page 

Layers 

• 

• 


22 

Paroxysmal Changes of Level 

4 1 

Lead Ore in Kansas 

• 

• 


5 i 

Peat .... 

# 

76 

Leavenworth Coal Mines 

• 


49 

“ Forming in Age of Man 

4 i 

Lignite in Kansas . 

• 

. 


49 

Periods .... 


29 

Lime 

• 



16 

Permian in Kansas 


45 

Limestones 

• 

• 


22 

“ Period 


34 

“ in Kansas 

• 

• 


49 

Plant Life, Action of, on Rocks 

67 

Loamy Soils . 

• . 

• 


75 

Plaster of Paris 


19, 50 

Low Bottom Soils . 

• 

• 


80 

Plesiosaurus . 


36 

Lower Carboniferous in Kansas 


44 

Post-Tertiary in Kansas 


47 

a •*« 

Period 


34 

“ Period 


38 

“ Silurian 

. 

. 


30 

Potash .... 


16 

Lycopodiums— Carboniferous 


33 

Prairie Decreasing in Kansas 

79 






Pterodactyl 


36 

Magnesia 

• 

• 


16 

Ptiddingstone 


21 

Mammalian Age—Life and Rocks 

37 , 38 

Pyrenees, Mass of 


12 

Mammals— Cenozoic 

. 

. 


37 

Pyrites in Kansas Coal 


48 

“ Mesozoic 

. 

• 


36 

Pyroxene 


17 

Man, Age of . .... 39 

Man, Age of, Life and Rock Form- 

Quartz .... 


16 

ations . 

• 

. 


40 

Rain Drop Prints . 


23 

Man, First Appearance of 

• 


40 

Reptiles — Carboniferous 


34 

Marble, Granular . 

, 

• 


21 

Mesozoic 


36 

“ Quarries . 

• 

f 


3 i 

Reptilian Age 


36 

Marls 

• 

• 


76 

Ripple Marks . 


23 

Massive Structure 

, 

• 


23 

Rock Crust 


M 

Mastodon 

, 

• 


38 

“ Layers, Formation 


1 3 

Megatherium 

• 

• 


38 

“ “ Position . 


24 

Metamorphic Rocks 

• 

• 


19 

" “ Total Thick 

ness 

14 

Mica 

• 

• 


17 

“ “ Upheavals 


25 

“ Slate 

• 

• 


20 

Rocks, Classification of 


*9 

Minerals . 

• 

# 


15 

“ Crystalline 


20 

Mineral Wells 


• 


65 

“ Definition of 


15 

Molds 


• 


69, 76 

Formed by Life 


26 

I\j[oorbed Pan . 

• 

• 


.78 

“ Fragmental 


21 

Moraines 

• 

. 


60 

“ Igneous 


*9 

Moss, Adhesion to Quartz-rocks 


68 

“ Metamorphic 


19 

Muck 

• 

. 


69 

“ Sedimentary 


l 9 

Mud Cracks . 

• 

• 


23 

“ Stratified . 


22 






“ Unstratified 


23 

Newfoundland Banks 

• 

• 


63 

Rootlets, Action of, on Rocks 

68 

Niobrara, Fossils of, in 

Kansas 


47 




Nitrogen of Plant-food 

• 

• 


85 , 9 ° 

Salt in Kansas 


50,51 






“ Upper Silurian . 


3 i 

Ocean Soundings . 

• 

• 


12 

Sand, Wearing Action of 


63,64 

“ Wearing Action 


• 


13,58 

Sandstones 


21 

Oriskany Formation 

• 

• 


32 

of Kansas 


50 

Osage Coal Seam . 

• 

• 


49 

Sea Border Formations 


39 

Outcrop . 

• 

• 


25 

SeaWeeds — Silurian . 


30 

Oxide of Iron 

• 

• 


16 

Second Bottom Soils of Kansas 

80 











9 6 


INDEX. 


Secular Changes in Level 
Sedimentary Rocks 
Selenite .... 
Serpentine 
Schistose Structure 
Shales .... 
Shaly Structure 
Shell Marl 
Sigillarids 

Silica .... 


Silt. 

Silurian Age . 

“ “ Life and Rocks 


cf 


Slate . 

Slaty Structure 
Soapstone .... 

Soda. 

Soils, Absolute Weight of 
“ Alluvial 

“ Analysis of, Chemical 
“ “ Mechanical 


Page 

4 1 

*9 

18 

23 

21 

23 

76 

34 

j6 

53 

29 

3 °. 3 1 
20 
23 

*7 

16 

77 
73 

85 

86 


“ Calcareous . 

“ Classification of . 

“ Clayey . ... 

*' Colluvial . 

“ Drift. 

“ Exhaustion of 
“ Fertility of ... 

Formed by Action of Frost 
“ “ “ Air in Motion . 

Soils Formed by Changes of Tern 

perature . 

Soils Formed by Decaying Vege¬ 
tation ...... 

Soils Formed by Living Plants 
“ “ “ Moving Ice 

“ “ " “ Water . 


7 6 

71 

75 

74 

72 
89 

83,86 

56 

63,64 

56 

69 

67,68 

59-63 

57,58 


“ Solution 


64-6 


'' Gravelly .... 74 

‘ Heavy and Light ... 76 

" Loamy . . ... . 75 

*' Now Forming ... 70 

“ Origin of .... 55 

“ Peaty.76 

“ Preparation of. for Crops . 87, 88 

“ Sandy . . 75 

“ Sedentary . . . . 71,72 

“ Specific Gravity of . . 77 

“ Transported .... 72 

“ Worn-out .... 89 


Page 


Sponges — Silurian ... 30 

Strata.22 

Strata, Conformable and Uncon- 

formable ..... 25 

Strata, Inclined at River Mouths 25 

Upheavals of . . 25 

Stratified Rocks .... 22 

Strike.25 

Talc.17 

Talcose Granite and Slate . . 20 

Tapir.37 

Temperature, Changes of, in Soil 

Forming.56 

Terrace Epoch .... 39 

Tertiary in Kansas ... 47 

“ Period .... 37 

! Tiffin Kansas Coal ... 48 

j Tilth.78 

j Time, Length of Geological . 41 

“ Table of Geological . . 42 

Tobacco as an Exhausting Crop . 89 

Topeka Coal Seam ... 49 

Transported Soils .... 72 

Trap. - . 21 

“ Dikes.31 

Tree Ferns — Carboniferous . 33 

“ Trunks in Coal Beds . . 24 

Triassic Period .... 36 

Trilobites — Silurian ... 30 


Unconformable Strata . ' . 

Unstratified Rocks 
Upper Carboniferous Period 
“ Coal Measures of Kansas 
Upper Silurian . 

Valleys, Formation of . 
Vegetation, Decaying; Action on 

Rocks. 

Vein Structure . . . . 


25 

23 

34 

45 

3 1 

12 

69 

24 


Water, Hard.65 

“ Moving, Wearing Power of 57, 58 

Weathering.66 

Weight of Soils .... 77 

Whales — Cenozoic . . . 37 

Wolf—Cenozoic .... 38 

Worn-out Soils - 89 

Zinc Blende in Kansas ... 51 















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